* Helga G. Pataki is possibly the deepest, most well-rounded female child character ever to set foot in Western Animation. From negligent [[WordofGod alcoholic]] parents, to putting all of her faith in Arnold... The list goes on and on. Her voice actress, Francesca Smith, actually won a Young Artist Award for her portrayal of Helga.
* Helga nonchalantly starts a conversation about painter Edward Hopper when she first goes into therapy with Dr. Bliss. Her deadpan expression and tone of voice imply that she doesn't even consider it a big deal that she's only nine and knows so much about fine art-- she's not bragging or anything of the sort. Just making small talk.
* In the Veterans Day's episode, Grandpa Phil narrates how he beat up Hitler; although he admits it wasn't Hitler and states he actually beat up [[http://en.wikipedia.org/wiki/Joseph_Goebbels Joseph Goebbels]], someone who was probably worse than Hitler. The rest of his story was even much more awesome, with Phil tricking several Nazi soldiers into eating spoiled meat, and opening a clear path for the Allies to invade Berlin. [[spoiler:Arnold doubts all of this, but Phil later proves the latter part by showing him a bust made in honor of his "single-handedly [winning] the Battle of the Bulge".]]
* Helga memorizing ''RomeoAndJuliet'' in one night and pulling off the performance with no rehearsal whatsoever. Even ThePowerOfLove can't fully account for that one.
** [[FridgeBrilliance Certainly not]]; Helga has been shown to be ''very'' intelligent in many episodes. She could have achieved that even without being motivated by her love for Arnold.
* The freakishly huge amount of character development! For one thing, Chocolate Boy starts out as just a chocolate junkie, but then he gets his own episode, where he goes from being comic relief to being a chocolate addict with a back story (in an episode that perfectly parallels many real-life drug stories). There were characters like Tucker, who were one episode wonders, but still managed to get character development into just eleven minutes of airtime. Helga started the show out as a total douchebag who stalked Arnold, but her dysfunctional family made her into an epic tragic love story, all leading up to HOTC! Everyone living in the boardinghouse got their own episode at some point! Brainy is the only character who really never got character development, but his lack of character development totally worked bacause he is the ULTIMATE creeper! Ironically, the show's main character, Arnold, is the only character to really undergo any flanderization (turning into the city's savior in later episodes), but even he had an epic backstory and to top it off, being the city's savior is totally badass!
** Brainy did manage to get some expansion via WordOfGod and AllThereInTheManual, though.
* Arnold's explanation to Grandpa and the other adults in "The Vacant Lot" for why he and his friends just overturned a dumpster full of garbage into the aforementioned vacant lot:
-->'''Arnold:''' You see, this is how the lot looked before we cleaned it up. Before we turned it into Gerald Field - and before you guys kicked us out.
-->'''Gerald:''' So if ''you'' want your vacant lot so badly, you can have it just the way ''we'' found it: a dump.
* In "Das Subway", Grandma is found meditating in her karate gi when she hears news of a subway breaking down, the very same one Arnold and many others are trapped in. She decides to take matters into her own hands and suits up commando style and searches for the subway.
* Arnold '''finally''' getting back at Helga in "Girl Trouble". Sure, it gets him in trouble thanks to DoubleStandard, but this clearly shows that there '''is''' a difference between NiceGuy and ExtremeDoormat.
* Stoop Kid finally leaving his stoop, jumping off the stoop when Harold makes fun of him for being afraid to leave his stoop and chasing him while saying "COME HERE FAT BOY! I'M GONNA ROLL YOU DOWNTOWN!" Also a funny moment. Harold's OhCrap expression just sells the awesomeness.
** That was the ''second'' time. He actually managed to leave (with Arnold's help) before Harold's scene. Speaking of, Harold apparently was on vacation and missed said scene, making the chase [[LaserGuidedKarma all the more awesome]].
* Gerald learning to ride a bike and winning the race in "Gerald's Secret".
* In ''Olga Gets Engaged'', Helga putting aside her feelings of resentment towards Olga and acting like a sister by getting rid of her lying, manipulative fiance. How does she do it? She catches him right after he finished talking to another girlfriend over the phone, reveals that she knows what he's really like, and when he counters that no one would believe her because of how jealous she is of Olga, Helga offers to redial his other girlfriend and tell her ''all'' about Olga. What really sells it is the guy's OhCrap look and Helga's smug smile as she holds her finger above the redial button.
* "Hey Harold!" has Harold telling Sid and Stinky off for making fun of his crush on Big Patty, which overlaps with CrowningMomentOfHeartwarming.
-->'''Harold''' (''to Sid and Stinky''): Stop it! You guys don't know what you're talking about. Her name's not Big Patty, it's Patty. And she's not clumsy and she's not dumb. Not only that, she's smart and she's nice and she's funny. I must be crazy to listen to you guys. Why do I care what you think? The only thing that matters is what I think. And what I think is I like Patty! And if anybody has a problem with that, ''I'll beat you up so bad it won't even be '''FUNNY'''!''
** Big Patty had a habit of bringing these out in others. Rhonda got hers by doing the same thing to a couple of upperclassmen in another episode. She even threatens to ''beat them up'' if they don't leave Patty alone.
* Hell, the series opens by giving Arnold one.
-->''I'm crazy, and you should never hit a crazy person.''
** For context's sake: Harold wanted to fight Arnold and the entire episode has Arnold stressing out over this impending problem. That quote is one part of the method of how he fixes it; he claims he's crazy. [[http://www.youtube.com/watch?v=dGTFO6rAPmU The]] [[Music/JamesBrown other part?]]
*** Best of all? ''[[DefeatMeansFriendship This endears Arnold to Harold.]]''
* Lila of all people gets one in "Big Sis," after Helga's attempt to ruin her and Olga's day by sabotaging their horse-drawn carriage turns nasty. One of the wheels flies off, throwing the driver, and the horse goes crazy - dragging the carriage along the ground and running uncontrollably at breakneck speed. Olga starts panicking, but it turns out the ex-farm girl Lila is used to this sort of thing. So what does she do? Leap from the careening carriage onto the horses back in a single bound, grab the reins and pull the horse to a stop. Even Helga can't do anything but gape.
* In one episode, Phoebe is turned into a laughingstock when she accidentally farted during a school assembly and became a shut-in because no one (except Arnold) would let her live it down. After her classmates and Mr. Simmons fail to cheer her up, Arnold manages to convince her to come back to school. That isn't the awesome part. The awesome part came when Phoebe marched on stage during another assembly and called out the entire student body for turning her into a one-dimensional joke, admitting that even she would've laughed if it had been someone else, but that it's not fair for all her hard work and accomplishments to be treated like nothing all because of a simple, human response.
-->'''Phoebe''': (to the school) I'm not that one who has anything to be ashamed of. ''You'' are.
* Bob calls Arnold an orphan during a Parents' Day competition where Arnold bring his grandparents, which visibly hits home for him. In retaliation, Helga tells Phil how to take him down during the final part of the competition.
* In ''Harold vs. Patty'', Harold loses to Patty in the Hillwood City Arm Wrestling Tournament. Sid and Stinky ''once again'' proceed to make fun of Harold losing to her. Harold decides he's had enough of their rudeness and starts shouting at them. (Doubles as a [[SugarWiki/FunnyMoments Funny Moment]].)
-->'''Harold:''' ''(yelling)'' SO WHAT IF I LOST TO A GIRL?! Patty's the best arm wrestler-
-->''(he grabs Sid and Stinky by their shirts)''
-->'''Harold:''' -in the whole city and ''she's my friend!'' I'm proud to lose to her, and if anyone has a problem with that, ''I'll pound them!''
-->''(Harold smacks Sid's and Stinky's heads together and they fall to the floor)''
-->'''Sid and Stinky:''' Ow...
* In the episode wherein Miriam proceeds to screw up her and Helga's road trip, Miriam pulls one of these with a mechanical bull riding competition. Helga can't watch because she thinks Miriam will fall right off... yet she manages to hold on twice as long as anyone else, wins, and impresses all of the manly man cowboys in there. The episode ends with a Heartwarming moment wherein Helga is so impressed with Miriam it's implied they bond.
* The fact that, after all these years, due to fan request, [[http://comicbook.com/2015/11/23/nickelodeon-developing-hey-arnold-tv-movie/ "The Jungle Movie" is officially happening]], ''and'' [[http://www.comingsoon.net/tv/news/694849-voice-cast-announced-for-hey-arnold-the-jungle-movie with most of the original voice actors]] [[RoleReprisal returning!]] Better late than never.
* "What's Opera, Arnold?" is 11 minutes of pure AwesomeMusic.