Characters / Hey Arnold!

This is a list for the large and varied cast of Nickelodeon's Hey Arnold!.
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Students of P.S. 118

Voiced by: J.D. Daniels (pilot); Toran Caudell (season 1 and "What's Opera, Arnold?"); Phillip Van Dyke (seasons 2 and 3); Spencer Klein (seasons 4, 5, and The Movie); Rusty Flood ("Helga on the Couch" and "Parents Day"); Alex D. Linz ("April Fool's Day" and "The Journal")

The titular main protagonist.
  • The Ace: He can do anything. By the time of the movie, most of the neighborhood believes he can save them from having to sell up and move. And he does.
  • Adorably Precocious Child: Arnold is one of the most mature animated pre-teens ever imagined.
  • All-Loving Hero: He never opts for violence, and rather have everyone get along.
  • Anime Hair: It's spiky, and lampshaded a lot throughout the series. In fact, it's so iconic, that's it's weird to see him have it combed or hidden beneath a hat ("Helga Masquerade", "Married").
  • Belligerent Sexual Tension: With Helga.
  • Blithe Spirit: Most of the time, he does some miracle with someone's life.
  • Characterization Marches On: He was more eccentric and naive early on. Midway in Season 3, this began to change (although he's still a bit dense).
  • Chick Magnet: Arnold has had three girls like him over the series.
  • Cool Loser: Subverted. He sometimes finds himself at the butt of his classmates' jokes or abuse for no good reason, but he otherwise is always included in their group activities and, one-on-one, gets along well with almost all of them most of the time.
  • Cloud Cuckoo Lander: In the early seasons, anyway, this went away halfway through the first season.
  • The Conscience: To everyone, especially in later seasons.
  • Dead Guy Junior: He was named after his mother Stella's late father.note 
  • Dogged Nice Guy: When he realizes that he likes Lila.
  • The Everyman: Eventually in the later seasons.
  • Flanderization: He started out as a good-natured kid that sometimes made mistakes, but as the seasons went on, he turned into an incorruptible advice-giving saint.
  • Four-Temperament Ensemble: The Phlegmatic.
  • Generation Xerox: In "Girl Trouble," it's revealed his grandparents had a relationship very similar to the one he has with Helga when they were younger.
  • Girl of the Week: Although some crushes have lasted through at least a season (Ruth McDougal and Lila Sawyer), he's had minor crushes not far in-between, like Maria, a sixth grader and Miss Filter, a substitute teacher.
  • Green Eyes: According to a poem by Helga.
  • Hair of Gold, Heart of Gold: Spiky, blond hair + Nice Guy + All-Loving Hero.
  • The Heart: His kindness and determination are what's keeping the town together.
  • He Really Can Act: Both in-universe and out; in "Eugene, Eugene" he's cast as the villain of the titular musical and does a surprisingly good job at it.
  • Heroes Want Redheads: He has a crush on the auburn-haired Ruth and later on the bright redhead Lila. But according to Phoebe in "Ruthless," Ruth's hair is chestnut.
  • Heroic B.S.O.D.: In the episode, Parents Day when Big Bob makes fun of Arnold's missing parents by calling him "Orphan Boy". Arnold then gets depressed for the rest of the day until he goes to sleep and realizes how much his grandparents have filled the gap his real parents left.
  • Heterosexual Life-Partners: With Gerald.
  • Humiliation Conga: Happens to him in the episode "Arnold Betrays Iggy", when he was forced to wear bunny pajamas in public. There's a reason why this is the most despised episode of the show.
  • Ideal Hero: High morals, Nice Guy, and willing to help anyone, even those who don't deserve it.
  • Instant Expert: While it wasn't ever stated how long his martial arts lessons took, he became a Bruce Lee tier Badass without taking a lifetime of training.
  • Living Emotional Crutch: Helga says she would probably go crazy if it weren't for Arnold.
  • Loving a Shadow: With Ruth, but also in general, he easily falls in love without knowing his beloved.
  • Luminescent Blush: Gets this a lot in "Timberly Loves Arnold", where Gerald's little sister has a crush on him.
    • Gets this a bit too in "Arnold Betrays Iggy", when he thinks back to Iggy wearing bunny pajamas.
  • Masculine Girl, Feminine Boy: Feminine Boy to Helga's Masculine Girl.
  • Meaningful Name: It was confirmed by Craig Bartlett that his last name is Shortman. He's one of the shortest kids in his class, being shorter than a good number of his friends such as Gerald, Helga, Sid, Lila, Eugene, etc.
  • Morality Chain: To any character who's on the edge of making an immoral decision, especially Helga.
  • Nice Guy: His defining character trait. Even when he's not the focus of an episode, he'll usually be the only one who won't make fun of the episode's protagonist.
  • Nice Hat: He's almost never seen without his little blue hat.
  • No Respect Guy: As shown in "Deconstructing Arnold", his classmates, until the end, don't realize how much wise impact he has on their decisions until after they told him to buzz off with his goody goody righteous personality.
  • Oblivious to Love: Arnold is incredibly dense when it comes to figuring out Helga's crush on him. Seriously, he buys any flimsy excuse Helga comes up with to cover up her secret. The one time he didn't buy her excuses was in the movie, and even after Helga flat-out tells him she loves him, he still has a hard time believing it.
  • Only One Name: The creator almost confirmed that his last name is Shortman, and it's Played for Laughs.
    Announcer: And the winner The last name appears to be smudged.
    Stinky: That must be you, Arnold, on account of you're the only Arnold in the entire school.
  • Only Sane Man: Amongst his class mates, though Gerald isn't that far behind.
  • Orphan's Ordeal: He can shrug off most insults, but calling him an orphan will cut him deep. Real deep. Heck, even Helga objects against the idea. And whenever the anniversary for his parents' abandonment approaches, he goes dim and it's the only time of the year he wants to be left alone.
  • Pink Girl, Blue Boy: Blue Boy to Helga's Pink Girl.
  • Precocious Crush: In season 1, he had a crush on Ruth P. McDougal, a sixth grader. In "Crush On Teacher", a season 2 episode, he develops a crush on his substitute teacher.
  • Raised by Grandparents: Since he was a baby, Arnold was raised by his paternal grandparents.
  • Shorter Means Smarter: One of the shortest kids in his class and also one of the smartest.
  • Spoiled Sweet: To a much lesser extent than Rhonda and Lorenzo, since he's not actually rich, but he has the coolest room only a kid his age could dream about. And he's the absolute nicest and most compassionate guy on the show.
  • Strong Family Resemblance: He gets his facial looks and oblong shaped head from his mother, albeit his blond hair is from his father.
  • Technology Porn: His bedroom, which boasts a glass ceiling and any number of fold-out implements operated by remote, including the bed.
  • Tiny Schoolboy: He is the shortest boy out of his group of friends and fits with the adorkable type.
  • Took a Level in Badass: In the episode where Pookie teaches him martial arts.
  • Tragic Keepsake: His hat, which was given to him by his parents. When he loses it in one episode, he's determined to get it back.
  • Wide-Eyed Idealist: Always believes in the best possible outcome.
  • Wise Beyond His Years: To the point that just about everyone on the show, including adults and even authority figures, have come to him for advice.

    Helga G. Pataki
Voiced by: Francesca Marie Smith; Katie Bartlett ("Helga on the Couch")

A resident bully at Arnold's school who actually has a deep infatuation for the titular character.
  • Accidental Pervert: When she snuck into Arnold's room, she was stuck between the the wall the couch folds into. She ended up seeing Arnold disrobe, even though she didn't mean to.
  • Act of True Love: Her sacrifices in Arnold's Christmas and Hey Arnold! The Movie definitely count as this.
  • Anti-Hero / Anti-Villain: Depending on the episode. Earlier episodes tended to use the latter, while later episodes mostly had her be the former.
  • Aww, Look! They Really Do Love Each Other: With Olga.
  • Beauty, Brains and Brawn: The Brawn to Lila's Beauty and Phoebe's Brains.
  • Because You Were Nice to Me: Helga fell in love with Arnold because he was the first person in her life that noticed her and treated her kindly. In somewhat of an inversion, this is why she treats Arnold like garbage.
  • Belligerent Sexual Tension: With Arnold.
  • Beneath the Mask: She pretends to hate Arnold to hide her true feelings for him, and only expresses said feelings when she's alone. Or she thinks so, and Brainy teleports behind her.
  • Betty and Veronica: The Veronica to Lila's Betty for Arnold's Archie.
  • Big Ol' Unibrow: Helga has a thick, black unibrow.
  • Blonde, Brunette, Redhead: The Blonde to Phoebe's Brunette and Lila's Redhead.
  • Breakout Character: Helga grew in popularity due to her compelling Character Development. By the end of the series, most people would think she was the main character instead of the football head due to how much spotlight she had. In fact, the show was meant to have a sequel specifically geared around Helga as the main focus in high school.
  • Brilliant, but Lazy: Though not a perfectionist like Olga, the aptitude test shows she is nearly as competent.
  • Broken Bird: Of the badass variety. She mentions in one episode that she would probably go crazy if it weren't for Arnold.
  • Cannot Spit It Out: And when she did it in The Movie... she took the chance Arnold gave her to deny it.
  • Catch Phrase:
    • "Criminy."
    • "Move it, Bucko!"
  • Cerebus Retcon: Much of her background becomes unfunny after "Helga on the Couch".
  • Clingy Jealous Girl: She often tries to ruin Arnold and Lila's time together because she wants to be the one going out with Arnold.
  • Consummate Liar: When she has to put up an act, like amnesia in "Beaned" or blindness in "April Fool's Day", she pulls it off very convincingly. Other times, she's an expert at hiding her feelings for Arnold which makes him completely oblivious in the first place.
  • Chromatic Arrangement: Pink to Phoebe's Blue and Lila's Green.
  • Cute Bruiser: A nine-year-old girl who can kick butt.
  • Dark and Troubled Past: Her early childhood had her being raised by two parents (who are one way or another pretty screwed up) doting all of their time to Olga and ignoring Helga. Needless to say, this resulted in Helga becoming a Broken Bird with other major emotional issues.
  • Deadpan Snarker: Helga is by far the most sarcastic character in the entire series.
  • Deuteragonist: The series also takes a heavy focus on Helga, revolving around her home life, friendships, and love for Arnold.
  • Double Standard: Abuse, Female on Male: If her and Arnold's genders were reversed, her abusive tendencies towards Arnold wouldn't be quite as funny.
  • Drama Queen: Even taking into account her usual hamminess and issues, she's usually the first person to crack up and go melodramatic in a crisis. (Ironic, considering she's considered the toughest girl in school behind Big Patty.)
    (when stuck on the other side of town) "Walk!? It'll take days! We'll freeze to death! WE'LL GET EATEN ALIVE BY PIGEONS! Or worse... rats!"''
  • Even Evil Has Standards: Does some nasty things to Arnold, but takes major offense to her father calling Arnold an orphan within ear shot of him. In "Curly's Girl", Helga calls out on Rhonda for embarrassing Curly after dumping him while pretending to be Curly's girlfriend.
    Helga: I think Miss Rich and Fancy did a number on him. (Referring to Curly.)
    Rhonda: May I borrow the black paint?
    Helga: (Paints a heart with the black paint.) Perfect, it'll match the color of your heart.
    Rhonda: (Annoyed) Excuse me!
    Helga: You heard me Cruella.
    • On top of that, once she found out that Summer was using Arnold for personal gain (with the intent on dumping him afterwards), she focused all her efforts on exposing her for his sake.
  • Evil Laugh: Has a very impressive one. Not as psychotic as Curly's (but then, who could be), but she gets points for once doing it in a theatre, with ominous music and everything.
  • Evil Plan: She explicitly refers to them as such, and she has a ton of them. They nearly always fail in ways that harm her and help those she schemes against.
  • Failure Is the Only Option: Her Anguished Declaration of Love in The Movie. Arnold ends up confused about it.
  • Femininity Failure: In "Helga's Makeover", she tries to be a girly girl to attend Rhonda's sleepover but reverts to her old self after refusing an avocado cream mask.
  • Forceful Kiss: Gives a big one to Arnold in The Movie.
  • Four-Temperament Ensemble: The Choleric.
  • Freudian Excuse: The reason for her violent behavior is because she feels neglected by her parents and she feels she has to be aggressive to get any respect.
  • Genius Bruiser: She is already fairly known among her classmates as a formidable bully. She's also a talented writer/poet, and quite intelligent for her age.
  • The Glorious War of Sisterly Rivalry: With Olga.
  • Hair Decorations: She always wears her trademark pink bow, presumably because Arnold complimented it when they first met.
  • Hates Being Touched: Or does she?
    Arnold: (After Helga finds his hat.) Thanks Helga! Thanks a lot! (hugs her)
    Helga: (Sighs dreamily before switching back to bully mode.) Yuck! Who said you could touch me?
  • Heterosexual Life-Partners: Her and Phoebe - mirroring Arnold and Gerald.
  • Hidden Depths: Aside having a Hidden Heart of Gold, she's really good at poetry for a nine-year old.
  • Hidden Heart of Gold: When she sometimes performs sacrifices for Arnold's happiness, or when she shows genuine kindness for Phoebe.
  • Hilariously Abusive Childhood: At least until "Helga on the Couch".
  • Hypocrite: What Helga feels and how Helga acts are always opposite things.
  • I Call It "Vera": Named her fists "Ol Betsy" and "The Five Avengers."
  • Implied Love Interest: Regulated to this, considering we never got The Big Damn Movie that, among other things, makes her and Arnold an Official Couple.
  • Improbable Hairstyle: Her hair looks like brooms.
  • Inferiority Superiority Complex: The reason for bullying other children, and Arnold, is to cover up her crush for him and not be bullied by other children for her exterior, plus that her home life is bad enough as it is. Claimed by herself during her gushing sessions about Arnold, she finds it very hard to overcome her shyness and doesn't quite know how to express her feelings since she had never been shown genuine affection (save Arnold) her whole life.
  • In Love with Love: Requited or not, pining itself is important to her.
  • Jerkass Façade: She does care about people, even if she doesn't show it.
  • Jerk with a Heart of Gold: She's mean, but has compassion deep down, even helping Arnold out of love several times.
  • The Lad-ette: A pre-teen version.
  • Large Ham: A running gag is her tendency to break into overly melodramatic monologues whenever she does anything she regrets, as well as villainous monologues when she's scheming. Often complete with theatrical music.
  • Like Parent, Like Child: Personality-wise, she actually has a lot in common with Big Bob, but Helga is much more articulate and emotional.
  • Little Miss Snarker: A nine-year-old girl with the dry wit of someone thrice her age.
  • Love Confession: Finally confesses her love to Arnold in The Movie.
  • Love Confessor: Confesses her secret to Lila in "School Play" and Dr. Bliss in "Helga on the Couch".
  • Loving Bully: The poster girl. Despite being a bully towards Arnold, she's madly in love with him.
  • Masculine Girl, Feminine Boy: Masculine Girl to Arnold's Feminine Boy.
  • Meaningful Name: Craig Bartlett chose Helga's name to emphasize her two sides:
    • "Helga" sounds very much like "hell girl", emphasising Helga's mask.
    • The name actually means "holy, sacred, successful", which emphasises Helga's hidden softer side.
  • Motor Mouth: She can really rattle off when she wants to, particularly when giving orders to Phoebe.
  • Mysterious Middle Initial: What precisely the "G" stands for is never revealed in-series; it's actually short for "Geraldine", as a tribute to then-Nickelodeon executive Geraldine Laybourne.
    • Considering how many times she's diminuatively called Gerald "Geraldo"...
  • The Nicknamer: She has a name for everybody.
  • Offhand Backhand: Helga frequently does this to Brainy. So often, that the one time she didn't punch him, he proceeds to punch himself in the face.
  • Perpetual Frowner: About 90% of her screentime has her frowning.
  • Pet the Dog: Several times, like in "Arnold's Christmas".
  • Phrase Catcher: "Whatever you say, Helga." Usually from Arnold (but occasionally from other characters) when she tries to browbeat her way out of situations. Arnold typically means it disbelievingly (aware that she's putting on an act) while everybody else is just being dismissive.
  • Pink Girl, Blue Boy: Pink Girl to Arnold's Blue Boy.
  • Pink Means Feminine: Subverted. She wears a pink dress as well as a pink bow in her hair but she's rather tomboyish.
  • Pitbull Dates Puppy: Helga is a rough, short-tempered and violent bully and she's completely in love with the kind-hearted, friendly and compassionate All-Loving Hero Arnold.
  • "The Reason You Suck" Speech: Helga is pretty good at these; she gives a pretty cutting one to Miriam about her being a "lousy mom", and one to Harold after he gets them lost.
  • Shadow Archetype: Helga is, ironically, Brainy's shadow.
  • She Cleans Up Nicely: Most of the time she doesn't care how she looks, but when she tries (and knows what she's doing) she looks gorgeous.
  • Single-Target Sexuality: Never shows the slightest interest in anybody but Arnold.
  • Single Woman Seeks Good Man: Her feelings for Arnold started when he shared his umbrella with her in the pouring rain and gave her his snacks in preschool. Throughout the series, Helga comments on how she loves his noble, kindhearted side.
  • Slapstick Knows No Gender: Very often. Deconstructed in "Helga on the Couch".
  • Sour Outside, Sad Inside: Helga is a cynical, always frowning kid. But that's mostly due to her sad childhood.
  • Spotlight-Stealing Squad: More episodes focused on Helga than any other character except for Arnold, and that's not including the many Arnold/Helga episodes.
  • Stalker Shrine: She built a shrine of Arnold that provides the Trope picture, including pictures she took him.
  • Stalker with a Crush: To Arnold. She has a shrine, a statue made out of his chewed bubblegum, and several books of poetry dedicated to him.
  • Stealth Expert: Has broken into the boarding house a total of seven times throughout the show's run. All occasions wearing her usual pink and white clothes. There was also the episode where she attempts to sabotage Lila and Olga's friendship where she dressed accordingly.
  • Stepford Snarker: Due to her backstory.
  • Strong Family Resemblance: Unfortunately, she gets her looks from her father, making her not so attractive.
  • Tomboy and Girly Girl: Tomboy to Phoebe and Lila's Girly Girl.
  • Tomboy with a Girly Streak: For all her tomboyish and violent personality, Helga always wears pink dresses, her room is filled with girly stuff and is a hopeless romantic.
  • Took a Level in Jerkass: She's crueler than usual in "Girl Trouble" and "Helga and the Nanny".
  • Took a Level in Kindness: At the end of "Arnold & Lila" and "Summer Love", and especially in "Arnold's Christmas".
  • Town Girls: The Butch to Phoebe's Neither and Lila's Femme.
  • Tsundere: Type A. She bullies Arnold outwardly but Gushes over him when she believes to be alone.
  • The Unfavorite: Helga is often ignored by her parents in favor of Olga.
  • Unknown Rival: Lila has no idea that Helga hates her at all, let alone why. Ironically she likely wouldn't want to be considered Helga's rival for Arnold's affections at all, since she doesn't reciprocate.
  • Unsympathetic Comedy Protagonist: She's often abrasive, and gives others (especially Arnold, her secret crush) a hard time. However, many of her flaws stem from an unhappy childhood as The Unfavourite. Often times, she still remains the Only Sane Man among classmates, lamenting their stupidity.
  • Vitriolic Best Buds: Type 1 with Phoebe. As Helga is bossy, while Phoebe just goes along. The two have a close friendship despite this.
  • Vocal Evolution: As her voice actress aged, Helga's voice deepened to the point that she sounds like a grown woman in the last few episodes. Oddly, it actually fits her character better.
  • "Well Done, Daughter!" Girl: She wants her the approval and attention of her parents (particularly Bob), but she rarely ever gets it due to being The Unfavourite.

    Gerald Johanssen
Voiced by: Jamil W. Smith

Best friend to Arnold.
  • Aww, Look! They Really Do Love Each Other: Like Helga, he clashes with his older sibling, Jamie O., but in "Jamie O. in Love", Jamie O. gets a girlfriend, causing Jamie O. to act like a happy Extreme Doormat, which Gerald takes advantage of, but when it turns out she is just using him, Gerald begrudgingly tells him the truth.
  • Beehive Hairdo: It's apparently an exaggerated hi-top fade, a style that was popular in the 90s.
  • Berserk Button: He gets really angry with Jamie O when he thinks he's trying to "steal" Chloe.
  • Beta Couple: Is often paired with Helga's best friend, Phoebe.
  • Black Best Friend: To Arnold.
  • Brutal Honesty: He doesn't bat an eye to tell Arnold what he thinks of his opinions.
  • Deadpan Snarker: The snarkiest character, next to Helga.
  • Foil: The main reason Arnold is the main protagonist instead of Gerald is because Arnold is much more serious than he is. Furthermore, hhe dresses in blue and is a blonde while Gerald dresses in red and is a brunette.
  • Heterosexual Life-Partners: With Arnold.
  • The Lancer: The more fun-loving best friend to the much more serious Arnold.
  • Large Ham: Any time he's in front of a crowd. Does everything from reciting cheesy Urban Legends to reading a list of fun things to do on Saturday with all the passion and soul of a gospel preacher.
  • Lovable Jock: He's into sports but he's still likable and not a jerk.
  • Only Sane Man: Along with Arnold, he's more down to earth than the rest of the fourth grade class and some of the adults as well.

    Phoebe Heyerdahl
Voiced by: Anndi McAfee

Best friend of Helga. Half Japanese girl who was born in Kentucky but moved to the city at a very young age.
  • Adorkable: A nine-year old nerd with glasses and a friendly personality.
  • Asian and Nerdy: She's half Japanese, and a bookworm with the highest grades in the class.
  • Beauty, Brains and Brawn: The Brains to Lila's Beauty and Helga's Brawn.
  • Berserk Button: She seems to have a mild one connected to when someone outperforms her academically or socially. In "Phoebe Cheats," she plagiarizes a poem for a contest presumably because Sheena got a higher grade than she did, and because she wasn't chosen as a Student of the Month.
  • Beware the Nice Ones: Pushing her around too much is not a good idea.
  • Blonde, Brunette, Redhead: The Brunette to Helga's Blonde and Lila's Redhead.
  • Brainy Brunette: The Smartest girl her class and gets Straight As.
  • Broken Pedestal: She was crushed when she realized Ronnie Matthews was a shallow jerk.
  • But Not Too Foreign: Shown to have an Asian father and white mother.
  • Catchphrase: In response to Helga asking her to do something: "[verb]-ing!" In particular, there's...
  • Characterization Marches On: In the first season she was a lot more of a Satellite Character to Helga, to the point of more or less being her shadow and not having much character herself. Later seasons fleshed out her personality more and made her less of a "minion" type.
  • Child Prodigy: Getting straight A's in all subjects in school at age 9 makes her this.
  • Chromatic Arrangement: Blue to Helga's Pink and Lila's Green.
  • Dropped Glasses: Got knocked off of her once when she was trying to be hall monitor. Unfortunately they got stepped on before she could find them.
  • Extreme Doormat: To Helga. She also has one of these moments in "Ms. Perfect," when she participates in the initial tormenting of Lila. When she gets skipped ahead to the Sixth Grade, she is "befriended" by a group of girls who just want Phoebe to do their homework for them. Helga even points out they're just using her.
  • Foil: To Helga, being rather calm while she's rather aggressive. In addition, Phoebe is the shortest student in her class while Helga is fairly tall. Also, she dresses in blue while Helga dresses in pink.
  • Heterosexual Life-Partners: With Helga. They're best friends and she's one of the few people who can stand her.
  • Hidden Depths: She's great with a fencing sword and speaks fluent Japanese. Both traits are nurtured by her Japanese-American dad. Also, in "Phoebe Skips" Helga realizes that Phoebe is simultaneously the only girl in school patient enough to really understand her, while also being the only one devious enough to willingly go along with all her pranks.
  • Knight Templar: As a hall monitor. Snaps out of it at the end of the episode.

    Rhonda Wellington Lloyd
Voiced by: Olivia Hack

One of the most popular kids in school and self-proclaimed "fashion queen", Rhonda is spoiled, rich, obsessed with fashion, and a bit of a snob, but she does have a friendly side that comes out quite often. Her best friend is Nadine, but she's often seen hanging out with Arnold and the gang. It's implied that she and Harold like each other, and Curly likes her too... much to her chagrin. She's also a surprisingly good football player.
  • Alpha Bitch: Very often thinks she's better than everyone because her family's rich.
  • Belligerent Sexual Tension: With Harold, as implied by several episodes that pair them up.
  • Break the Haughty: All the freaking time, but most notably Rhonda's Glasses and Rhonda Goes Broke.
  • Cool Kid And Loser Friendship: The cool girl to Nadine's loser.
  • Fallen Princess: This is the subject of a couple episodes (most notably "Rhonda's Glasses" and "Rhonda Goes Broke"), but she's always back on top by the end.
  • The Fashionista: What she aspires to be.
  • Characterization Marches On: Just like the other kids her personality was undefined and she was more of a background character, however by the second season she is shown to be a rich spoiled fashion queen.
  • Heroic B.S.O.D.: When her family becomes poor in "Rhonda Goes Broke" - specifically, when everybody finds out that she's poor - Rhonda has a major one, spending all her time in her room miserably crying. Luckily, Arnold reboots her when he talks some sense into her and asks if being rich is all she's about.
  • Hypocritical Humour: In one episode, she tells Nadine she has to have a "three shoe rotation" in order to continue hanging out with her, even though all the characters in the show, including Rhonda, have a Limited Wardrobe.
  • Jerk with a Heart of Gold: She does have a good heart under her vain, self-centered exterior.
  • Large Ham: She's pretty prone to this when she breaks into histrionics, especially in the episode "Rhonda Goes Broke".
  • Lovable Alpha Bitch: Despite often being a typical spoiled rich girl, she does have a kind side. Not only does she always do the right thing in the end, but her best friend - Nadine - is middle-class.
  • Meganekko: In "Rhonda's Glasses", where she ends up having to wear glasses after a vision test says she needs them.
  • Noodle Incident: According to "Egg Story", something happened between her and Harold at the Cheese Festival, but we never find out what.
  • Rich Bitch: On her worst days.
  • Spoiled Sweet: On her best days.
  • Tomboy and Girly Girl: Girly Girl to Nadine's Tomboy.
  • The Unreveal: So...what happened between Rhonda and Harold at the Cheese Festival?
  • Unwanted Glasses Plot: Gets them in Rhonda's Glasses, but later replaces them with cooler glasses, and eventually contacts.
  • Vocal Evolution: Her voice became more mature in later seasons, this is because her voice actress Olivia Hack was going through puberty. Unlike others on this list, it's barely noticeable.

Voiced by: Lauren Robinson

Nadine is Rhonda's best friend, even though they couldn't be more different. She is fascinated by bugs and arachnids.

    Harold Berman
Voiced by: Justin Shenkarow

A fat kid who's been held back a few grades. Occasionally, a bully.
  • Bare Your Midriff: He's so fat his shirt doesn't fit properly.
  • Berserk Button: Yeah, keep calling Patty "Fatty Patty." That's a good way to induce Harold's biggest screaming meltdown of the series.
  • Big Eater: One of his main traits, as Helga once claimed he ate half his weight in chocolate.. He even gets into trouble in one episode because he steals a ham from Mr. Green. When confronted by his parents, he replies, "I was hungry!"
  • The Big Guy: Being the oldest of the kids, he takes the role as the strongest of the gang.
  • Big Ol' Unibrow: Like Helga, he also has one of these.
  • Big, Thin, Short Trio: Among his friends Sid and Stinky, he's the big one.
  • The Bully: In the first season, he was this to Arnold, although Wolfgang eventually took the role of the bully instead. He still has shades of it later on.
  • Butt Monkey: Has his moments.
  • Catch Phrase:
    • "Madame Fortress Mommy!" Adlibbed by Justin Shenkarow once to Craig and everyone's amusement. They kept writing it in after.
    • "Aah Mommy!"
  • "I was hungry" can count, as he says it in several episodes.
  • Dumb Muscle: The strongest of the kids, but is 13 years old because he was Held Back In School.
  • Held Back In School: Is about 13 years old (old enough to have a bar mitzvah) but still in 4th grade.
  • Hidden Depths: Usually with Harold what you see is what you get. But after a mix up in "The Aptitude Test" results in him believing he's a genius, he starts listening to classical music, correctly solves a math problem in his head, and designs a gazebo/bonsai garden for his family's rooftop.
  • Hypocritical Humor: In Helga's Masquerade, he makes fun of Helga for having a Big Ol' Unibrow, despite the fact that he has one himself.
  • Informed Judaism: His Jewish background wasn't mentioned until the episode in which he tries to run away from his own bar mitzvah, though prior to that, it was established he had a mom who acted like a Jewish Mother.
    • In fact, in one of the old claymation shorts, he attends church with Arnold.
  • I Want My Mommy: Happens occasionally, usually whenever he gets scared.
  • Jerkass: In the first season.
  • Jewish Mother: His mom Marilyn fits some of the stereotypes, most notably being a My Beloved Smother.
  • Kind Hearted Cat Lover: Surprisingly, but "Harold's Kitty" has him adopting a seemingly stray cat and fawning over it.
  • Large Ham: "AAH MOMMY!!!"
  • Likes Older Women: It depends if Patty was held back like Harold or if she's the same age as him.
  • Nice Hat: Rarely seen without it like Arnold.
  • No Indoor Voice: Less so whenever he's bummed about something.
  • Outof Character Moment: In Stinky's Pumpkin when Mr. Simmons asks the class what the hullabaloo about spring is, Harold of all people answers by saying "Love is in the air". Although it was said with a tone of sarcasm in it.
  • She Is Not My Girlfriend: With Patty.
  • Ship Tease: With Patty, and Rhonda in some episodes.
  • Took a Level in Kindness: He's kind of a dick in the first season, but he eases up in later seasons showing compassion towards others such as his friends Sid and Stinky.
  • Vague Age: The writers seem to flip-flop between having Harold a few years older, or the same age as Arnold and his friends. In one episode he is shown to have gone to preschool with them yet in another he turns 13. He could have failed preschool though.
  • Vocal Evolution: The pitch of his voice remained consistent, but developed a raspier sound post-season 1.

Voiced by: Sam Gifaldi; Taylor Gifaldi ("April Fool's Day")

A paranoid boy in a hat.
  • Cool Loser: He's got style even if he isn't popular.
  • Gag Nose: Has a very big nose.
  • Hollywood Voodoo: Thought he once killed Principal Wartz with a voodoo doll made of soap.
  • Iconic Item: His white Beatle boots.
  • Jerk with a Heart of Gold: His spotlight episodes tend to display him as a paranoid Large Ham who frequently lets his imagination get the best of him or digs himself in too deep and needs Arnold to save him. That said, he does try to make amends for the things he does when he realizes he's gone too far.
  • Karma Houdini: He and Stinky receive absolutely no comeuppance after learning Iggy's secret, spreading it throughout the school, and then bragging about taking pictures at Arnold's final ordeal to get Iggy's forgiveness. Arnold in contrast, ends up the one having to dress up in a bunny costume. This is one of the reasons why the episode is not well-received.
  • Large Ham: Episodes centering around him bring this out, especially "Sid the Vampire Slayer" and "Sid's Revenge."
  • My God, What Have I Done?: When he thinks he's killed Principal Wartz with a voodoo doll carved from soap.
  • Nice Hat: Like Arnold, rarely seen without it.
  • Only One Name: The second most prominent example on the show, behind only Arnold himself.
  • Pet the Dog: He's not all bad, however. In one episode, he gets into trouble with Big Gino. When Arnold tells Sid he doesn't have to do what Big Gino says, Gino orders him to give Arnold a swirlie. Sid stands up to Gino to take Arnold's place.
  • Poisonous Friend: To Stinky.
  • Properly Paranoid: Exemplified in his spotlight episodes where he goes on to freak out over something he thinks would happen and do everything he can to prepare, like having a nightmare where Stinky was a vampire after seeing a vampire movie. He then goes on to read about vampires and to learn about how to deal with one.
  • Screams Like a Little Girl: Especially in his Spotlight episodes.
  • Those Two Guys: Is this with Stinky a good number of times.
  • Took a Level in Jerkass: Around Season 3
  • With Friends Like These...: Shares this status with Stinky as two of the worst of the kids besides Helga and Harold. Whereas Helga and Harold both have considerable amounts of depth, Sid and Stinky frequently display Lack of Empathy and turn on their so-called friends. Notably whenever an episode focuses on Harold, Sid and Stinky whill be there to mock him until he finally gives a Big "SHUT UP!" and threatens to beat the snot out of them.

    Stinky Peterson
Voiced by: Christopher P. Walberg

A kid with a thick Southern accent.
  • Big, Thin, Short Trio: When paired up with his friends Sid and Harold, he is the thin one.
  • Butt Monkey: Can be this at times.
  • Catch Phrase: "This really bites." and variations of it was prevalent throughout the series. In seasons 3, 4, and 5, he also said "Willikers!"
  • Characterization Marches On: In Season 1, he was more of a mindless lackey to Harold and wore spiky arm-bands. Later on, he was revealed to be a lot nicer and no longer wore the arm bands.
  • Country Mouse: In fact, he lives in a wood cabin in the middle of the city.
  • Deep South: His family is from Arkansas. However, it is revealed in "Stinky's Pumpkin" that he was actually born in Hillwood.
  • Gag Nose: Has a ridiculously big pointy nose.
  • Green Thumb: In "Stinky's Pumpkin", he successfully grows an enormous pumpkin that is big enough for him to comfortably sit in.
  • I Just Want to Be Special: Often wishes he was able to be good at something.
  • Jerk with a Heart of Gold: He can be obnoxious when he's around Sid and Harold, but his spotlight episodes show that he's more civilized.
  • Karma Houdini: Being entirely at fault for Arnold's ordeal in Arnold Betrays Iggy yet nothing happens to him.
  • Simpleton Voice: One episode even had him star in a commercial line-up for Yahoo! Soda because of it.
  • Trademark Favorite Food: Lemon pudding.
  • With Friends Like These...: Shares this status with Sid. Although, his spotlight episodes do show he has some depth to him.
  • Simple-Minded Wisdom: He declined the million-dollar contract because he thinks pride is more important than money.
  • Strong Family Resemblance: He looks a lot like his Dad.
  • Those Two Guys: Can be this alongside Sid in a good chunk of episodes he's featured in.
    • Could be this with Harold also, on a few occasions such as "Deconstructing Arnold".
  • Took a Level in Jerkass: Much like Sid, his behavior started worsening in Season 3.note 
  • Toxic Friend Influence: He's nicer when he's not with Sid and/or Harold.
  • Unfortunate Names: See below. Though the only person in the series who ever seemed to find it to be this was the director from "Stinky Goes Hollywood".
  • Who Names Their Kid "Dude"?: It has been stated in his spotlight episodes that "Stinky" just happens to be his real name. The director from "Stinky Goes Hollywood" even lampshaded it.
  • Verbal Tic: "I reckon".
  • Vocal Evolution: His voice actor went through puberty, and thus, Stinky's voice deepened over time.

    Eugene Horowitz
Voiced by: Christopher J. Castile (early season 1); Jarrett Lennon (later season 1); Ben Diskin (seasons 2, 3, and 4); Blake McIver Ewing (season 5 and The Movie)

An extremely unlucky kid.
  • Adorkable: His friendly attitude and Butt Monkey status has made him beloved by fans.
  • Ambiguously Gay: His bedroom is decorated with rainbows and unicorns and he seems to enjoy dancing and musicals. He also reacts with horror that he has to kiss a girl in "Romeo & Juliet". (The other boys do too, but Eugene specifically states, "I'd rather not kiss a girl," while the others just laugh.) Also, this dialogue from "Ghost Bride":
    Sid: (to Curly) I can't believe you pulled such a dirty trick on us!
    Eugene: (to Curly) I can't believe how nice you look in that dress.
  • Ambiguously Jewish: His last name is Horowitz, a Jewish surname. "Eugene" was also a popular name for American Jews in the early 20th century, and his father's name "Nate" is a nickname for "Nathan," a name of Hebrew origin.
  • Beneath the Mask: "Roller Coaster" shows that despite always trying to look on the bright side, he is depressed because of the other kids considering him a jinx.
  • Born Unlucky: He was also born on a Friday the 13th.
  • Butt Monkey: Almost every episode has him in some form of pain.
  • Catch Phrase: "I'm okay," said after something bad happens to him.
  • Ironic Name: His name means "born lucky".
  • The Jinx: The other kids think he is one of these, and Arnold often gets dragged into trouble when he tries to help Eugene or prove that he isn't a jinx.
  • The Klutz: Not just extremely clumsy, but is also just a bad luck magnet in general.
  • Nice Guy: One of the nicer kids in school.
  • The Pollyanna: He is almost always freakishly happy and optimistic, despite his luck issues.
  • Screams Like a Little Girl: Whenever he's about to get seriously hurt.
  • Stepford Smiler: In the episode, Married when he believes that Sheena will be his future wife.
  • Throw the Dog a Bone: Arnold often tries to invoke this, but each time life tends to yank the chain.
  • Wide-Eyed Idealist: Surprisingly, he tends to look on the bright side of everything, no matter how dense the situation is.
  • Youthful Freckles: To match his red hair.

    Lila Sawyer
Voiced by: Ashley Buccille

A poor country girl who transfers to the school.
  • All-Loving Heroine: Although she came off as an intentional parody.
  • Beauty, Brains and Brawn: The Beauty to Phoebe's Brains and Helga's Brawn.
  • Beneath the Mask: Not shown too much in the series, but in an interview Craig Bartlett said she had a hidden dark side. However, this calls for a reevaluation of pretty much all her scenes involving Arnold and his unreciprocated crush on her. Her dark side may have very well been there, just hidden under a veil of passive-aggressive sweetness.
  • Betty and Veronica: The Betty to Helga's Veronica for Arnold's Archie.
  • Beware the Nice Ones: It's made pretty clear by Word of God that she does have a dark side, though it's been hidden during the show's run.
  • Blonde, Brunette, Redhead: The Redhead to Helga's Blonde and Phoebe's Brunette.
  • Broken Ace: She's smart, funny and charming, but has a horrible home life and poor self esteem.
  • Chromatic Arrangement: Green to Helga's Pink and Phoebe's Blue.
  • Country Mouse: Compare her to Rhonda, and you'll know she fits.
  • Demoted to Extra: This happens very late in the show's run, so it's difficult to tell at first glance (especially since the episodes originally aired out of order and months or years apart), but after Arnold finally gets over her in "Timberly Loves Arnold"/"Eugene, Eugene!", she makes no further speaking appearances, including in The Movie. (Nobody was cast to play her in The Jungle Movie, either.)
  • Dude Magnet: She's popular with the boys.
  • Foil: To Helga, big time. A great deal of Lila's appearances, and the nature of Arnold's relationship with both, play up how Lila is everything Helga isn't. According to Craig Lila had a repressed dark side. So in addition, while Lila was sweet and innocent on the outside, but emotionally disturbed on the inside, Helga was mean and crazy on the outside, but kind and sophisticated on the inside.
  • Girlish Pigtails: Always sporting these.
  • Love Revelation Epiphany: In "Arnold & Lila", Lila starts to like Arnold only because Helga wrote "Arnold Loves Lila" on the wall and Lila assumed it had to be true. Arnold tells her he doesn't "like-like her" and Lila becomes very disappointed, but realizes she only came to "like-like" Arnold because she thought he felt that way about her. So when Arnold realizes he does "like-like her", Lila isn't interested in him anymore.
  • Manipulative Bitch: Not to an extreme, but there are times when, looking closely, you see Lila's rather sly. In a subtle way by expressions and choice of words. There's the question of her and Arnold's interactions, plus the fact that she reeled Helga in with no choice but to confess her secret rather impressively in "School Play". With Craig's claims of her having a locked dark side, it makes one wonder.
    • When asked about Helga and Lila becoming friends in the future (and if that meant that Helga accepts Olga as well) in The Arun Mehta Show Special With Craig Bartlett, which confirmed the idea was more of fan canon rather than actual canon that he's thought of, he had this to say -
    Craig: Helga and Lila have a really complex relationship because Lila has helped her keep her secret and helpe—and Lila's a bit of a player, you know, she kind of manipulates people in her—in her sort of innocent way.
  • Master of the Mixed Message: Offers a sort of unintentional hope spot for Arnold sometimes, but ends up emphasizing at the end that she does not "like-like him"
  • Missing Mom: She's only raised and supported by her father.
  • Nice Girl: An ever-so-sweet kind girl.
  • Out-of-Character Moment: Despite her kindness and sweetness in just about every episode, in "Phoebe's Little Problem", Lila makes a rude and bored face with the other kids while Phoebe is giving a speech.
  • Parody Sue: A sickeningly sweet parody of a Mary Sue.
  • The Pollyanna: Like Eugene, Lila is very optimistic. In fact, Helga tried to scare her out of the part of Juliet with bad costumes, violence, and stage fright, but she just sees the other side of those things.
  • Proper Lady: Her politeness is pretty much what makes her character going.
  • Redhead In Green: Usually because of the Limited Wardrobe.
  • Secret Keeper: Due to events in "School Play," Helga is forced to confide in her that she loves Arnold. (Naturally, before telling Lila, Helga threatened to strangle her if she ever told anyone.)
  • She's Got Legs
  • Shipper on Deck: Ironically, if mildly. She thinks Helga's crush on Arnold is "ever so sweet" and is more than willing to bow out of the way so Helga can orchestrate a kiss with him.
  • Stepford Smiler: Implied, according to Word of God.
  • Super Drowning Skills: She can't swim.
  • Tomboy and Girly Girl: Girly Girl to Helga's Tomboy.
  • Town Girls: The Femme to Helga's Butch and Phoebe's Neither.
  • Unrequited Love Switcheroo: In "Arnold & Lila", when Lila believes Arnold has a crush on her, she starts to like him too, but he "likes her, but doesn't like-like her". Once she gets the message, he really does start to "like-like her". Unfortunately, Lila decides that she now just likes him and insists in being Just Friends for the rest of the series.
  • Verbal Tic: "Ever so", "oh so", and "I'm certain that..."
  • What Does She See in Him?: For some reason, she goes completely head over heels for Arnold's cousin Arnie.
  • Youthful Freckles: To match her red hair.

    Thaddeus "Curly" Gammelthorpe
Voiced by: Adam Wylie; Steven Hartman ("Downtown as Fruits"); Haley Joel Osment ("Deconstructing Arnold"); Michael Welch ("Curly's Girl" and "Ghost Bride")

Psychotic kid with black hair and glasses.

Voiced by: Craig Bartlett

An otherwise taciturn mouth-breathing nerd who seems to have a thing for Helga.

Voiced by: Francesca Marie Smith

A geeky girl who does not like violence.
  • Abhorrent Admirer: She's good friends with Eugene, but while she's happy about Rhonda's marriage prediction in the episode "Married", Eugene's response is...less than enthusiastic.
  • Every Proper Lady Should Curtsy: When she was announced as having best report in "Phoebe Cheats".
  • Fragile Flower: Helga manages to convince her to drop out of Romeo and Juliet when she tells Sheena how bloody and sad the play really is.
  • Hair Decorations: Has pink hair clips.
  • Huge Schoolgirl: Easily the tallest girl in class; towers over many of the adult characters at only nine years old.

    Ruth P. McDougal
Voiced by: Lacey Chabert; Anndi L. McAfee

A sixth grade who is Arnold's first crush.
  • Chuck Cunningham Syndrome: In the first season, she was just a generic love interest for Arnold, but as Arnold grew more of a personality, Ruth faded out of the show without any explanation.
  • The Ditz: She thinks Arnold's secret note to her is from a famous poet, named Anonymous.
  • Satellite Love Interest: Her only role in the show is to be Arnold's crush early on. Effectively disappears after Arnold finds out that they have nothing in common.

    Patricia "Patty"/"Big Patty" Smith
Voiced by: Danielle Judovits

An ill tempered sixth grade girl who becomes Harold's friends.
  • Dull Surprise: How she speaks. All the time. Which contrasts Harold who is very dramatic and hammy.
  • Hair Decorations: Wears a blue bow.
  • Hidden Depths: Underneath that tough championship arm wrestler outer shell is a polite girl who volunteers at homeless shelters and knits.
  • Huge Schoolgirl: Her parents look like midgets next to her.
  • In-Series Nickname: Overlaps with Embarrassing Nickname. Most kids call her "Big Patty" even though as Harold says, "Her name isn't Big Patty, it's Patty!" Once people get to know and respect her, they drop the "Big."
  • No Guy Wants an Amazon: Played with. Sid and Stinky mock Patty because of her size, saying if they had to dance with someone like her, she'd probably crush them. But Harold, no small fry himself, likes Patty, not because he's an Amazon Chaser but because they have a genuine connection, one that leads to them spending all night just talking.
  • Proper Lady: Shockingly yes, if she would stop beating kids up. Then again she apparently only goes after people who have provoked her.
  • Secret Keeper: Implied- In "Helga vs. Patty", she makes an offhanded comment about Helga seeming fond of Arnold. When Helga angrily denies it, Patty just smiles knowingly.
  • Tomboy with a Girly Streak: She is Tough but can be a Proper Lady as shown in Polishing Rhonda.
  • True Blue Femininity: Generally wears Blue clothing.

Voice by Victor Cohn-Lopez

A wealthy student.
  • Early-Bird Cameo: His debut episode was supposed to show him as a new character, but he had already shown up in Arnold's Room and Gerald's Tonsils. Blame Nick's airing order.
  • My Beloved Smother: His mother is very overprotective.
  • Nice Guy: Like Arnold, Lorenzo is polite to his friends.
  • No Social Skills: In Rich Kid, it's shown that he has no idea how to goof off and be a kid.
  • Spoiled Sweet: He's as rich as Rhonda, and a friendly guy to boot.
  • Super OCD: Arnold even points out how he's always looking at his watch every five seconds. He does get over it.
  • Wise Beyond His Years: He's nine years old, but has the personality of a 30-year old businessman.

Voiced by Joseph Ashton

Arnold's popular classmate.
  • Cool Shades: Wears teal shades and is never seen without them.
  • Demoted to Extra: He was already pretty much an extra at the beginning of the show but he had his own episode with Arnold Betrays Iggy. After that episode's terrible reputation, though, he never had a major role again and only appeared in the background in a few episodes and only had a speaking part again 4 years later in the episode Gerald's Game'.
  • Flat Character: Iggy's main reputation during the time he was on the show was that he was considered the cool kid, though they never explain why.
  • It's All About Me: He doesn't care for the depths that Arnold is going through to earn his forgiveness, and he doesn't even care that he got the wrong guy in the end. In the end, Arnold Betrays Iggy was all about his pain and humiliation.
  • Jerkass: Shown to be one for what he puts Arnold through.
  • My God, What Have I Done?: What he realizes at the end of Arnold Betrays Iggy.
  • With Friends Like These...: More so than Sid and Stinky combined. Thankfully Arnold realizes this and breaks off his friendship with Iggy.

    Peapod Kid
Voiced by Jamil W. Smith

A kid dressed up as a peapod.
  • Mad Libs Catch Phrase: "Oh, my, that is terribly, terribly X."
  • Only Known by Their Nickname: He's called Peapod Kid because he has no real name given and he dresses as a peapod in the school play.
  • Ship Tease: In Married, Rhonda predicts that he'll be married to Nadine someday suggesting he has a crush on her.
  • Spoiled Sweet: He's as rich as Rhonda and a pretty nice guy as well.

The Adults

    Grandpa "Steely" Phil
Voiced by: Dan Castellaneta

Arnold's grandfather/Parental Substitute.
  • Annoying Younger Sibling: He acts like this to his older twin sister when she comes over to visit. This lowers after Arnold helps him and Mitzi make peace.
  • Badass Grandpa: Defeated Big Bob on in the Parent's Day episode. Also a decorated World War II veteran, even if he didn't really beat up Hitler (it was actually Goebbels). It is also said that he can bench 210 lbs, even at his old age and is as healthy as a man decades his junior.
  • Belligerent Sexual Tension: With Gertie when they were younger.
  • Cassandra Truth: In "Girl Trouble," he flat-out tells Arnold that Helga constantly teases him because she likes him. Arnold naturally doesn't believe him.
  • Cloud Cuckoolander: Not to the extent of his wife, but some episodes play this up to the hilt, such as the one where he believed himself stranded on a deserted island and confused a flock of ducks for his ancestors.
  • Cloudcuckoolander's Minder: Serves as this to Pookie when he isn't being one himself.
  • Cool Old Guy: He's nothing if not a great parent for Arnold, and he's more than willing to bend over backwards to help his grandson.
  • Generation Xerox: "Girl Trouble" reveals Phil was teased by Gertie the same way that Arnold is teased by Helga.
    • "Snow" also seems to imply that he had a similar relationship with his grandfather that Arnold has with him.
  • Genre Savvy: He often describes the plot templates in play.
  • Getting Crap Past the Radar: At least half the instances of it in this show come from him. Chief among them being that he's named after a type of dildo.
  • Grumpy Old Man: Not usually, but he has shown shades of this on a few occasions, usually when he is annoyed with the borders.
  • Noodle Incident: Phil was apparently an acrobat in a Russian circus.
  • Obfuscating Stupidity: Uses this on occasion, most notably in a flashback to his days in World War II where he tricks group of Germans who had captured him into eating spoiled meat.
    "It was then I realized that if I let the Major think he was smarter than me I could make him do anything I wanted..."
  • Savvy Guy, Energetic Girl: The Savvy Guy to Pookie's Energetic Girl. While he can be a little ditzy as well sometimes, she's this ten times more than him.
  • Those Two Guys: Despite how much he hates Oskar, the two have many scenes together throughout the series.
  • Vocal Evolution: His voice sounded more raspy and forced in the first few episodes. In the original pilot, Dan's voice sounded similar to what it would post-vocal evolution, but was more shaky.

    Grandma Gertie (aka Pookie)
Voiced by: Tress MacNeille

Arnold's grandmother.
  • Affectionate Nickname: Pookie.
  • Badass Grandma: An expert in karate and capable of rescuing a mistreated sea turtle and repairing the subway.
  • Belligerent Sexual Tension: With Phil in her youth.
  • Cloud Cuckoolander: Pretty much embodies this trope as she's often seen acting like a different stock character, such as a cowgirl or a karate master.
  • Cool Old Lady: She's respected for being fun-loving for her age.
  • Generation Xerox: In "Girl Trouble," it's shown that she and Phil had a relationship very similar to Helga and Arnold when they were younger. As part of the gag, Gertie in the flashback is voiced by Helga's voice actress.
  • Girlish Pigtails: In her youth.
  • Let's Get Dangerous: She saves the day when even Arnold fails. For example repairing the underground or stopping Bob's bulldozer.
  • Loving Bully: In her youth.
  • Never Mess with Granny: She's a black belt in karate.
  • Obfuscating Insanity: There are rare times where she behaves in an odd fashion - only to then imply it was just an act.
  • Only Known by Their Nickname: Usually referred to as "Grandma," "Pookie" or other nicknames. Her first name is mentioned as part of the Generation Xerox twist in "Girl Trouble."
  • OOC Is Serious Business: In "Parents Day," she acts like her usual fun-loving, crazy self. After seeing Arnold so depressed over his Parental Abandonment, however, she snaps out of the role she was playing and acts far more subdued.
    • Played for laughs during a heat wave; Arnold notes that the heat's so bad that even his grandmother is acting normal. Her wearing scuba gear and walking around like she does it every day when it starts raining is a sign that everything is going to be fine.
  • Savvy Guy, Energetic Girl: The Energetic Girl to Phil's Savvy Guy. While he can be a little ditzy as well sometimes, she's this ten times more than him.
  • Scatterbrained Senior: She is pretty much insane. Unlike most instances of this trope, played for laughs rather than drama.
  • Tsundere: In her youth.

    Olga Pataki
Voiced by: Nika Futterman

Helga's older sister and the parental favorite, much to Helga's dismay (and Olga's too, as revealed in "Olga Comes Home"). At first glance, Olga appears perhaps too perfect: Successful, pretty, smart, and sweet and kind to everyone. But she's actually dangerously neurotic, melodramatic and out of reality, due to having to constantly live up to her parents' (well, her father's, anyway) constant attention and ridiculously high standards.
  • Aloof Big Sister: Unintentionally this to Helga.
  • Aww, Look! They Really Do Love Each Other: With Helga in every single episode she appears in.
  • Bare Your Midriff: Her default outfit shows it off a bit.
  • The B Grade: Hasn't received an A- since third grade. In the "Olga Comes Home" episode, she cried for days in bed because she saw a B+ on her report card. Turns out, it was Helga who intercepted her report card and changed her grade out of jealousy.
  • Broken Ace: She seems to be perfect at everything, but underneath her façade she's incredibly broken due to her father's absurdly high standards for her.
  • Cool Big Sis: In the aptly-named episode "Big Sis", she becomes one to Lila through volunteer work. With her biological sister Helga, however...not so much, but only because Helga can't stand her. However, Olga's come through for Helga on several occasions. Averted in the episode where Olga becomes a teacher's assistant- she proceeds to tell the whole class that Helga used to wet the bed, then gives Helga a detention when she lashes out at all the teasing that follows.
  • Cute but Cacophonic: See The B Grade above
  • Embarrassing Nickname: To Helga- she insists on calling her "Baby Sister".
  • Extreme Doormat: She doesn't even tell her parents how she really feels about the high expectations she's felt she needs to live up to.
  • Fragile Flower: Her response to anything stressful is to freak out and burst into tears.
  • Friend to All Children: Regardless of what Helga thinks, her schoolmates love Olga.
  • Go-Getter Girl: A deconstruction. While Olga has good leadership skills and regularly gets straight As in college, she is held to extremely high expectation by her parents. Also, she is driven to a mental breakdown over a B grade (which Helga forges, mind you).
  • Nervous Wreck: Underneath her "perfect girl" façade.
  • Nice Girl: To everyone and shows no contempt toward anyone.
  • Parental Favoritism: On the good end of it, which turns out to not be so good for her, in reality.
    Olga: You must think I'm lucky, all the attention I get from them. I have to perform for them all the time like some kind of wind-up doll. I get really sick of it. You're lucky they don't even notice you.
  • The Perfectionist: Mainly because of Bob's high standards for her.
  • Stepford Smiler: Type A. She pretends to be happy around her family, when deep down, she's constantly stressed out from her parents' high standards.
  • Unknown Rival: She genuinely has no idea Helga has been competing with her for her whole life, and seems genuinely shocked when Helga tells Olga she can't stand her.
  • Zettai Ryouiki: Wears thigh-high socks to match her plaid skirt.

    Robert "Big Bob" Pataki
Voiced by: Maurice LaMarche

Father of Helga and Olga. Runs a local business aptly named "Big Bob's Beepers".
  • Abusive Dad: Emotionally to both daughters, but in completely different ways.
  • Accidental Misnaming: Consistently calls Helga by her sister's name, and almost always gets Arnold's name wrong.
  • Adaptation Dye-Job: He has gray hair in the series, but in the movie his hair is brown.
  • Big Ol' Unibrow: Where Helga gets hers from.
  • Depending on the Writer: Abusive jerkass or simply an ignorant boor who just doesn't understand how much trouble he's caused for his family? The latter characterization became steadily more common from Season 2 and onward. In the first season, he was portrayed as pretty much devoid of redeeming qualities.
  • The Dragon: To Scheck in the movie, in order to build a bigger Big Bob's Beepers. Though he defects from Scheck once he finds out that he's getting only 49% of the income.
  • Education Papa: Most of the pushing towards excellence that Olga received came from Bob's end, as he was the one who made it a big deal that she win so many awards and trophies, while Miriam just provided commentary. In the early seasons he even tried to shape Helga into following Olga's path.
  • Fat Bastard: Most of the time.
  • Gasshole: He belches and breaks wind on occasion.
  • Gosh Dang It to Heck!: Tends to say "Mother Hubbard," "Mother Goose," "Mother Scratcher," and "Heck".
  • Humiliation Conga: Helga was so disturbed by the "Orphan boy" line (see below) that during a gladiator-style event, she told Phil what Big Bob's weakspot was. Basically, she told him to go for the ankles, which sent Big Bob into a tub of gelatin - costing him the event and the overall win.
    • Basically any episode that accentuates his Jerk Ass qualities ends with him getting a solid block of hilarious karma dropped on his head. "Roughin' It" is another good example, where he ends up alone in his RV stuck with sunburn, swamped with bugs, and itching from poison ivy (not to mention having been electrocuted by his own faulty products earlier) while everyone else enjoys camping the old fashioned way.
    • He goes through another in "Summer Love". He sits in a lounge chair, gets sunburned, and has no one to take care of him, not even his wife whom he neglects. When he tries getting out of the house, he irritates his sunburn and gets a defeating blow from Miriam.
  • Jerk with a Heart of Gold: While he rarely shows it, he does love and care about Helga, and in some instances can help out other characters when needed. They even hint that he does care about his wife as well, especially in "Summer Love" when she told him about another man teaching her "the Watoosy".
  • Kick the Dog: His "orphan boy" line (referring to Arnold) in "Parents Day". It's so mean and insensitive that it would qualify as a Moral Event Horizon if he'd said it directly to Arnold (as it stands, he was talking to Helga and was just characteristically loud and uncaring about anyone else overhearing).
  • My God, What Have I Done?: In the Halloween Episode he was legitimately horrified when he realized he just attempted to murder Helga thinking she was an alien, calling himself a monster.
    • More so in Big Bob's Crisis after having a heart attack. It was actually gas.
  • Not So Different: Helga gets her more abrasive personality traits from Bob, which allows them to bond in several episodes.
  • Papa Wolf: In the Thanksgiving episode, Bob is ready and prepared to take out the tank to find the missing Helga.
  • Parental Favoritism: To Olga to the point that she would rather be neglected to avoid having to live up to his standards.
  • Parental Neglect: To Helga to the point of ignoring her existence when Helga was about to go to pre-school
  • Took a Level in Kindness:
    • "Big Bob's Crisis" was all about Bob realizing his high-stress life made him obnoxious, cruel and abusive to those around him - though he initially overcompensates by uprooting the entire family and becoming an Extreme Doormat, it ends with him deciding that he can be his old self while still being a little kinder and a little less stressed.
    • Double Subverted in the movie (which takes place after "Big Bob's Crisis"). He's all for getting rich off of the destruction of the neighborhood, until he finds out that Scheck's getting 51% of his company. He later offers to help Phil and the boarders to stop the bulldozers.
  • Wouldn't Hurt a Child: He may be a Jerkass like his daughter and use verbal abuse, but Bob draws the line when it comes to physically harming a child. In the Halloween episode he almost had Helga killed when he thought she was an alien, until he learns that the "alien invasion" was just her in costume for a theme party - at which point he was very distraught.
    • Also happens in "Save the Tree" when he refuses to bulldoze the kids' favorite tree because his own kid is up there.
  • Why Couldn't You Be Different?: To Helga.

    Miriam Pataki
Voiced by: Kath Soucie

Mother of Helga and Olga, Miriam is a depressed, constantly sleepy, seemingly ditzy housewife with an addiction to "smoothies" (Word of God confirms that all of these are signs that Miriam is an alcoholic, with "smoothies" as a cover-up for booze). It's not uncommon to find her sleeping in strange places. However, she can be very competent and intelligent, but unfortunately it seems that being married to Big Bob has really brought her down.
  • The Alcoholic: The show indicates she drinks a lot of "smoothies", but her slurred speech and forgetfulness imply "smoothie" is just a term for alcohol to get past the radar.
  • Alcoholic Parent: While they couldn't state it outright (since Hey Arnold is still a kids' show, despite the myriad of adult themes), Miriam is obviously a heavy drinker, with the show using smoothies as a metaphor for booze. If you look closely when she grabs some ingredients for her "smoothies", she grabs a bottle of Tabasco sauce and if "The Patakis" was made, it is informed she would be attending AA.
  • All Girls Like Ponies: In "Road Trip," she reveals to Helga that when she was a kid, she wanted to learn to ride horses, but her dad refused to let her, fearing she'd get hurt. Her response to this, surprisingly enough, was to become a champion mechanical bull-rider.
  • Blind Without Them: Implied during the few times she loses her glasses or is shown without them.
  • The Ditz: As a result of her drinking problem.
  • Drives Like Crazy: Due to her drinking, Miriam has had her license revoked. When she took over for Bob's beeper store and drove Helga to school, all the kids were worried that Miriam was driving again (meaning that the kids know that Helga's mom is either a Drunk Driver or just a very, very bad one).
  • Hidden Depths: She was once a world-class swimmer, won a bull-riding competition as a girl, and can run the family business better than Bob can if she wanted to.
  • Hypocritical Humor: Calls Helga 'weird' in one episode when she hears Helga manically laughing in her Stalker Shrine.
  • I Need a Freaking Drink: She'll occasionally say that she needs a "smoothie".
  • Mama Bear: In the Thanksgiving episode, Miriam is on the phone with the police and demands that they help find Helga. Note, this is one of the few times Miriam ever sounds angry.
  • My God, What Have I Done?: In "The Beeper Queen", when she realizes she's been neglecting Helga for her new job.
  • Odd Friendship: Develops one with Suzie in "Summer Love".
  • Verbal Tic: Often speaks in a slow, drawling voice. Justified as Craig Bartlett has revealed that Miriam is an alcoholic.

    Robert Simmons
Voiced by: Dan Butler

Fourth grade teacher at P.S. 118 starting in the second season, replacing the original Living Prop, Miss Slovak. Thinks of everyone and everything as "special".
  • Adults Are Useless: Specifically in the episode "Girl Trouble" when he doesn't punish Helga for bullying Arnold, yet he punishes Arnold for fighting back. Other examples include:
    • "Buses, Bikes, and Subways"—doesn't double-check his head count and is totally oblivious to the fact that two of his students are missing until the bus is back home.
    • "The Flood"—allows students to run riot for 3/4 of the episode and then tries to climb up a ladder during the storm for help, and ends up falling into several feet of water, meaning the kids have to save his butt.
    • "Aptitude Test"—mixes up two of the eponymous tests; doesn't bother to recheck the folders.
    • "On the Lam"—doesn't know his science closet was raided until informed on the evening news.
  • Ambiguously Gay: Played by an openly gay actor, loves the theater, and has a very delicate, effete personality. In fact, a character who may or may not be his partner even appears in the Thanksgiving episode.
  • Cool Teacher: He can be this when he's not being useless. In fact, his premiere episode, "New Teacher," was all about the kids realizing this after they gave him a hard time.
  • Imagine Spot: In "Principal Simmons", Mr. Simmons imagines what the school would be like if he was the principal, which features the kids all beings friends with each other, Helga and Brainy walking together with their arms around each other, Wolfgang giving Eugene a piggyback ride, Harold becoming smart, the kids eating healthy food and happy to be the principal's helper.
  • Ink-Suit Actor: A very glaring example on a show with otherwise very outlandish character designs; Simmons strongly resembles his voice actor, Dan Butler.
  • Nice Guy: One of the nicest adults in the series.
  • Non-Standard Character Design: Considerably less cartoony-looking than the other characters due to being based on a real person.
  • Oblivious to His Own Description: He is the only one who doesn't recognize his own Catch Phrase in Helga's parody.
  • Only One Name: It is strongly implied, but never explicitly stated, that his first name is Robert (in the Thanksgiving episode, he wrote a play that was based on his own life; we meet every character from the play in person later on except for him).
  • Selective Enforcement: In the episode "Girl Trouble," Helga relentlessly torments Arnold throughout the episode, and eventually Arnold gets sick of it and throws paint on her in retaliation. Mr. Simmons does nothing about Helga's bullying, but punishes Arnold for dumping paint, vocally expressing his disappointment in him.
  • Shipper on Deck: "Principal Simmons" implies that he thinks Helga and Brainy would make a good couple.
  • Wide-Eyed Idealist: His Imagine Spot is a good example of this.

    Alphonse Perrier du von Scheck
Voiced by: Paul Sorvino

The CEO of Future Tech Industries, Scheck is a greedy and heartless businessman who wants to tear down Arnold's neighborhood to build a gigantic, immaculate shopping mall. Only appears in The Movie, where he is the Big Bad.
  • Affably Evil: Appears to be this at first, but it fades over the course of the movie.
  • Big Bad: The main antagonist of the movie.
  • Big "NO!": After he sees that Arnold, Helga and Gerald have escaped - with the videotape that exposes him burning the document.
  • Corrupt Corporate Executive: Not only is he not above burning a document declaring the neighborhood a national landmark, the whole reason he wants to build the mall in the first place is to get revenge after his family name was sullied over the "Tomato Incident" that happened in front of Sunset Arms.
  • Evil Overlooker: On the poster and DVD cover of The Movie.
  • Knight of Cerebus: He's much more evil and played seriously than the other characters.
  • Man of Wealth and Taste: A small running gag has Gerald voice admiration for Scheck's suit.
  • Slasher Smile: Most notably when he's burning the document declaring the neighborhood a national landmark.
  • Soft-Spoken Sadist: His voice is pretty unassuming and even somewhat soothing for a villain, but he tends to lose this when he gets mad.
  • Villainous Breakdown: He starts out appearing as an affable but very weaselly businessman, but ends up as a raving madman who is perfectly willing to run over several people, including children, with his car.

Voiced by: Jennifer Jason Leigh

Only appearing in The Movie, Bridget is a sort of spy girl/superheroine who helps Arnold and Gerald save the neighborhood by supplying them with equipment and providing them a VCR to play the security tape exposing Scheck.

    Oskar Kokoshka
Voiced By: Steve Viksten

A lazy con artist and Suzie's husband.
  • Annoying Laugh: Eh heh heh heh!
  • Butt Monkey: He largely deserves it, too.
  • Funny Foreigner: Mentioned in one episode as hailing from the former Czechoslovakia.
  • Jerk with a Heart of Gold: He's selfish, lazy, and leeches off his wife. However, in the episode where he's forced to look after Baby Oscar, whom he initially resents but grows protective over, and there are times he feels guilty about leeching off Suzie.
  • Lazy Bum: When he finally does get a job delivering papers with Arnold's help, he's too lazy to even do that, making up excuses so that Arnold does it instead of him. It gets to the point that even Arnold calls him a "huge loser".
  • Lazy Husband: Lives off his wife and still expects her to do all the housework.
  • Man Child: Lazy and childish, Oskar often neglects responsibility.
  • Never Learned to Read: It's eventually revealed that he's illiterate. Arnold volunteers to teach him how to read.
  • Ugly Guy, Hot Wife

    Suzie Kokoshka
Voiced By: Mary Scheer

Oskar's loving wife who puts up with his laziness.
  • No Accounting for Taste: Although she fights with Oskar often and has kicked him out on more than one occasion, she always seems to forgive him, only to have him make the same mistakes again.
  • Odd Friendship: With Miriam in "Summer Love".
  • Parenting the Husband: Often does this to Oskar as he leeches off of her and gambles often. Suzie is the sole source of income, and is run ragged by her childish husband.
  • Ugly Guy, Hot Wife

    Ernie Potts
Voiced By: Dom Irrera

A short man who works as a demolition expert.
  • Fiery Redhead: Male example, although he is mostly bald.
  • First-Name Basis: Unlike most of the other boarders, Arnold calls him Ernie in later seasons, although he does call him Mr. Potts early on.
  • Hot-Blooded: He's very emotional.
  • The Napoleon: Shorter than Arnold, but very passionate about the demolition business.
  • Tiny Guy, Huge Girl: He develops a crush on a very tall model named Lola, and the two even date until they had a falling out due to Lola being uncomfortable with their difference in height, though she apologizes, and they remain friends at the end of the episode.

    Mr. Hyunh
Voiced By: Baoan Coleman, Randy Travis (singing)

An immigrant from Vietnam and a pretty nice guy.
  • Characterization Marches On: Mr. Hyunh is initially a stereotypical, high-tense Asian man who mostly panic and tends to yell the same thing over and over whenever there's trouble. Early into the show, this aspect of his character is lessened as they make him into more of a character and less of a stereotype.
  • Daddy Had a Good Reason for Abandoning You: Gave up his then two-year-old daughter to soldiers who were airlifting civilians to safety during the Vietnam War, so that she would be safe and have a better life. The only reason he couldn't go with her was that the soldiers could only take one person with them.
  • Determined Widower: Back in Vietnam, he was raising Mai all by himself, his wife nowhere to be seen. (It's possible she fell victim to Death by Childbirth, but this is never confirmed.) After he comes to America, he spends a good amount of time searching for his daughter.
  • Funny Foreigner: In earlier episodes where he would shout the same word over and over.
  • Hidden Depths:
    • Though he comes off as a somewhat overdramatic Funny Foreigner in most episodes, some (in particular the Christmas Episode) where he has A Day in the Limelight, show him to be more insecure and worried about his situation.
    • There's the episode where it's revealed he sings amazingly as a country artist. So much that Gerald was able to profit off of him for the episode before Hyunh chose "The Simple Things" of his life instead of the limelight.
    • He can play cello, guitar and trumpet quite well.
  • Large Ham: How he responds to frustrating situations.
    Mr. Hyunh: This lint. Your lint! I cannot keep cleaning up after you! I am not your mother! (beat) I'm not his mother!
    • In "The Vacant Lot", he was this at the end, shouting "Play ball!" 10 times in a row.
    Mr. Hyunh: Play ba-all! Play ball! Play ba-all! Play ball! Play ba-all! Play ball! Play ba-all! Play ba-all! Play ball! Play ba-all!
    Grandpa Phil: WILL YOU BE QUIET?!
    • And the time he dressed up as Juliet in order to help Romeo Arnold learn his lines in "School Play".
  • Last Name Basis: Even the adults at the Sunset Arms call him Mr. Hyunh.
  • Only One Name: See Last Name Basis above.

    Miles and Stella Shortman
Voiced by: Craig Bartlett (show creator) and Antoinette Stella (an episode writer)

Arnold's long missing parents.
  • Adventurer Archaeologist: Perhaps to make them not be exactly like Indiana Jones they aren't Archaeologists, but have other jobs that would mean they might spend most of their time in a South American rainforest. But they still manage to rescue an artifact from a Jungle Pirate anyway.
  • Battle Couple: If Phil's stories and Miles' journal is to believed.
  • Birds of a Feather: How they met. Miles overheard Stella talking about the clouds looking like ships.
  • Brainy Brunette: Stella has brown hair and is a Doctor/Scientist in botany.
  • Daddy Had a Good Reason for Abandoning You: They both left to help cure a deadly illness sweeping throughout the population of the South American country, particularly that of a secretive tribespeople who have helped them throughout the years who they owe their lives to. As Miles had written in his journal, they expected the trip to be a short one...
  • Happily Married: They were very happy together.
  • Parental Abandonment: Both left Arnold to be looked after by his Grandparents to depart on an important mission (though they did expect to come back).
  • Screaming Birth: To give Stella her dues she may have been angry at the time, but she manages to keep it together rather well for a woman giving birth in remote Jungle Temple whilst a volcano is erupting all around her!. Stella provides the picture for the page.
  • Whip It Good: Miles is extremely proficient with a whip, using it to tether two cable-cars together at one point to stop one from falling.
  • Why Did It Have to Be Snakes?: Miles really hates spiders.

    Principal Wartz
Voiced by: David Wohl

As you may have guessed, he's the principal of P.S. 118 and he's known to be harsh but has reasons to be. Throughout the show, Wartz often is seen taken punishments too far, even by following teachers but he has toned this down after realizing when he sees how the others handle order.
  • Ambiguously Gay: In "Sid's Revenge," he is shown to have a male roommate who cooks for him.
    • The man is seen in the kitchen next to a bag labeled "Hospital Home Meal Service," and he later calls Wartz "Mr. Wartz," so he was more likely just a hired cook.
    • He also has decidedly un-manly interests such as playing with figurines and following pop idols.
    • He seems to get a bit of Ship Teasing with Mr. Simmons on occasion, such as when they went out karaoke singing together.
  • Dean Bitterman: One episode has Mr. Simmons call him out for being too strict of a principal. And another has him suspend Arnold for two days because he told him he was being too unfair to Harold.
  • Disproportionate Retribution: In Suspended where Arnold begs him to let Harold back and Arnold just gets suspended.
  • Inherently Funny Words: "Slippage." To the point that the credits to that episode are a Stupid Statement Dance Mix of all the times he says it.
  • Jerk with a Heart of Gold: He’s harsh at times but he’s willing to negotiate if the situation can be resolved.
  • Last Name Basis: His first name is never revealed.
  • Man Child: Shown to be this as he is seen playing with toys at his work desk and sending fan mail to teen singing sensation, Ronnie Matthews.
  • Not So Above It All: Despite trying to put up the appearance of a stern, no-nonsense diciplinarian, he's not above playing with toys and shaking his groove thing while belting out some campy 70's karaoke.
  • Pet the Dog: He can be reasoned with, even letting a kid off the hook depending on the situation. He also has a set of toy animals on his desk in order to calm down and/or reduce the stress on any meeting he may have.
  • Properly Paranoid: Even if the kids have no interest in misbehaving, Wartz is often like this.
  • Stern Teacher: As a Dean Bitterman like principal.

    Willie the Jolly Olly Man
Voiced by: Dan Castellaneta

A mean, sadistic, downright crazy guy who works as an ice cream man.
  • Abusive Parents: Implied, seeing as he's employed by his father who appears to be, at best, apathetic and at worst emotionally/verbally abusive. This is probably part of why he's so nuts.
  • Aesop Amnesia: Subverted. In Career Day, Arnold teaches him how to properly do his job and avoid getting fired. In subsequent appearances he flip-flops from being the same jerkass he always was, and actually doing his job well.
    • When Grandpa Phil accidentally runs him off the road in Grandpa's Packard, he goes as far as to dress up in drag, and trick Phil into giving his address, so he can steal the Packard from him. He apologizes after he gets arrested, though.
    • He makes a small appearance in the movie, though, where he seems to be good at his job again.
  • Ambiguously Brown: Has tan skin.
  • Characterization Marches On: He didn't start out crazy.
  • CloudCuckooLander: He's apparently convinced in Grandpa's Packard that the start of his bad day was his dog laughing at him.
  • Freudian Excuse: In 'Career Day', Arnold finds out he's been fired from every single job he's had, and his Bad Boss is none other than his own Dad, who treats him with utter contempt.
  • Ironic Nickname: The Jolly Olly Man.
  • Jerk Ass: He'll drive off without giving kids their ice cream, not give them the right flavors, yell at them and treat them with no respect, or just outright ignore them.
  • Nice Hat: Mandatory because of his job.
  • No Social Skills: He was not aware there was anything wrong with his attitude, and views the children he serves as frightening. When his boss/father shows up saying that his numbers are down, he says it's not his fault that kids these days don't want ice cream. There was also a moment in Grandpa's Packard where he says that he was having a terrible day, one of the reasons being that the expiration date on his milk was wrong. He's not wrong, the milk was wrong. It'd be somewhat believable if it wasn't preceded by his dog laughing at him, and followed by a maniacal Grandpa Phil running him off the road on purpose.
  • Pet the Dog: He gives Arnold an 'A' at the end of 'Career Day' and a free ice-cream, as thanks.
  • Slasher Smile: Accidentally scares kids off with his smile when Arnold is trying to improve him.
  • Through the Eyes of Madness: We occasionally see how he views the world. In Career Day, he sees the city in black and white and nothing but slums, the kids as hyperactive creepy children, and his ice cream truck as a cage.
    • Grandpa's Packard shows that he views Grandpa's running him off the road as a malicious act against him, and not a mistake, complete with an evil looking Packard spewing flames and Grandpa Phil laughing maniacally.
  • Woobie, Destroyer of Worlds: In episodes like Career Day, it's implied that beneath all that crazy is a deeply, deeply damaged man.

    Vincent the Pigeon Man
Voiced by: Vincent Schiavelli

An outcast who lives atop an abandoned apartment block who prefers to be around pigeons more than humans.

    Mr. Marty Green
Voiced by: James Keane

A local butcher that runs for councilman in Mr. Green Runs.
  • Berserk Button: NEVER throw a board over a pothole and say it's fixed, especially after he's called you countless times requesting to get it fixed.
  • Beware the Nice Ones: If Councilman Gladhand had bothered to actually fix the pot hole; he'd probably still have a job.
  • Defrosting Ice King: When Harold steals a ham from his shop, Mr. Green punishes him by forcing him to work for free for a week. Harold grows to like the job, though Mr. Green sees him as trouble. Then at the end, Mr. Green warms up to him when he offers to help out during a busy hour.
  • Expy: Of the title character from the movie, Marty.
  • Large Ham: When Arnold is looking for a musical act for a dance, Mr. Green offers his singing voice which really stands out to say the least.
  • Nice Hat: His butcher hat.

    Coach Jack Wittenburg
Voiced by: James Belushi

A local coach who's forgetful in names and only has limited experience, often needing Arnold to help him out.
  • Disproportionate Retribution: During a basketball game, he tells the kids that they have to pass the ball to his son Tucker so he can score. When Arnold ignores his advice, explaining that he wasn't open and had to make the shot himself, Coach Wittenburg benches him for the rest of the season.
  • Drill Sergeant Nasty: His method of coaching involves screaming at the players, until Arnold comes in.
  • A Father to His Men: He does care about the kids he's coaching as he really wants them to succeed. And when he tries to organize a Synchronized Swimming Team, he goes to Arnold and friends, knowing they've been there for him in the past.
  • Hot-Blooded: His competitiveness with his wife, Tish can get pretty out of control sometimes.
  • Large Ham: Much like your typical super-competitive coach.
  • Malaproper: Constantly speaks in this manner as he often has no idea what the stuff he talks about means.
  • The Nicknamer: To the kids, he constantly calls Arnold, Arnie.

Other Kids

Voiced by: Grant Hoover

A cousin of Arnold's who is disconcertingly similar, but much stranger and less attractive. Naturally, Lila falls head over heels for him.
  • Ambiguous Disorder: Arnie displays several signs of ASD, particularly Asperger's Syndrome, such as odd hobbies (counting things, reading ingredient labels [along with seemingly knowing what they are and how to pronounce them]) and collections (specifically balls of lint and "plain flavored" gum), displays muted outward signs of emotion, and seems to have difficulty in social interaction. These traits lead some of the other characters to think he is "dull" and "slow."
  • Bizarro Universe: The episode "Arnold Visits Arnie", in which just about all of the side character kids and main cast members get an eerily similar doppelganger with a completely opposite personality.
  • Cloudcuckoolander: His hobbies include collecting lint and reading the ingredients off of packaged products.
  • Country Cousin: He lives in the country in contrast to his city cousin.
  • Creepy Child: Not as much as Curly but his bizarre personality makes him rather weird to most people.
  • Creepy Monotone: Though the "creepy" is entirely up to the viewer's discretion.
  • Dead Guy Junior: Assuming Arnie is Arnold's maternal cousin (which is likely, since Phil certainly doesn't treat him like his own grandson, and both boys have the football head which Arnold inherited from his mother), then Arnie was also named for their shared grandfather, Stella's late father.
  • Joke Character: Reportedly a character created as an in-joke response to Off Model animation.
  • Kavorka Man: Big time. He isn't that good looking yet Lila would rather be with him than Arnold.
  • Mirror Universe: In "Arnold Visits Arnie", to some degree. That is, of course, if you believe that it isn't normal for Arnie to go Axe Crazy on his cousin and/or want to include the character alignments of the citizens of Arnie's hometown.
  • Murder the Hypotenuse: In "Arnold Visits Arnie" towards the end of the episode. It turns out it was just a dream, though.
  • Nightmare Face: Arnie gets one, also a result of the fiendish dream. Almost makes you wonder about Arnold a little...
  • Oddball Doppelganger: To Arnold.
  • Ugly Guy, Hot Wife: Arnie's less-than-attractive guy to Lila's, and later Lulu's (though this turned out to be All Just a Dream) rather pretty girl.

    Rex Smythe-Higgins III
Voiced by: Joey Stinson

Rex Smythe-Higgins III is the grandson of Grandpa Phil’s rival Rex Smythe-Higgins I and is the same age as Arnold. He’s often had to complete against Arnold and is a Polishing school alumni.
  • Friendly Rivalry: Despite his rivalry with Arnold, they both are on good terms.
  • Jerk with a Heart of Gold: He may be arrogant at times, but he doesn’t like cheaters and would rather play fair in completion, "Tour de Pond". In "The Pig War", he helps Arnold save Abner from being cooked by the British Pig War team after learning that he's Arnold's pet.
  • Nice Hat: A blue cap.
  • Pet the Dog: Almost literally. Once he learns Abner is Arnold's pet, he's quick to compare him to his own Scottish terrier, Pepe. Later Pepe makes a cameo in "Polishing Rhonda."
  • The Rival: To Arnold in a few episodes.
  • Wise Beyond Their Years: He’s actually much more mature than his grandpa considering he’s still a kid.

Voiced by: Toran Caudell

The leader of the fifth graders and bullies the fourth graders around.
  • The Bully: Much worse than Harold and Helga.
  • Genius Bruiser: He's surprisingly crafty, from devising plans for Trash Can Day to making sure Chocolate Boy doesn't eat chocolate for a month.
  • Hidden Depths: He mentions that he needs to take oboe lessons until four.
  • Jerk Jock: Shows shades of being an unpleasant jock, especially "Longest Monday".
  • Karma Houdini: Most of the time, he and his fifth graders succeed without punishment.
  • Not So Above It All: He's very superstitious.
  • The Rival: Acts this way towards Arnold and the other fourth graders.
  • Younger Than They Look: It's hard to imagine that he's only fifth grade considering he has an appearance and a voice of a high school student.

Voiced by: Phillip Van Dyke

Another bully introduced in 'New Bully on the Block', explaining he was at Juvenile prison and only recently got out.
  • The Bully: Like Wolfgang, Ludwig is a bully who picks on the fourth graders. Furthermore, "New Bully on the Block" was written for the express purpose of having all three Arnold's in a single episode.
  • Chuck Cunningham Syndrome: Never appears again after "New Bully on the Block", possibly due to the poor reception the said episode received.
  • Karma Houdini: Like Wolfgang, he gets away with bullying the fourth graders.
  • Only One Name: And he's named after a famous musician just like Wolfgang.
  • Real Men Wear Pink: He tells Arnold he has to go to his tap-dancing class when Arnold tries to arrange a meeting between him and Ludwig.
  • Remember the New Guy: Averted- Arnold vaguely remembers Ludwig, but the show acknowledges he's never been seen before by explaining he went to Juvie before the series began.
  • We Hardly Knew Ye: Goes right in hand with One-Shot Character.

    Chocolate Boy
Voiced by: Jordan Warkol

A young boy with an unhealthy obsession with chocolate.
  • Big Eater: Of anything chocolate. But now he's obsessed with radishes.
  • G-Rated Drug: He's obsessed with chocolate like a crack addict. Until the end where he gets addicted to radishes.
  • Hidden Depths:
    • In his spotlight episode, he reveals the reason he's so addicted to chocolate is because he misses his nanny. His parents told him chocolate was bad for him, but his nanny secretly gave him some until she had to leave.
    • Plus in Oskar Can't Read? he's shown to be able to read through an excerpt of A Tale of Two Cities with no trouble, even for someone seemingly in kindergarten.
  • Only Known by Their Nickname: Everyone calls him Chocolate Boy, and his real name is never revealed.
  • Serious Business: His obsession with chocolate is so bad that it makes him do stupid things just to get some. He once went two weeks without eating any chocolate so he could win a ten-pound bag of the stuff. And he eats it all in one sitting. And in Buses, Bikes, and Subways he sneaks onto a field trip to the chocolate factory.
  • The Pig Pen: Often has chocolate stains all over him.
  • Trademark Favorite Food: Chocolate. Now it's radishes.