Spoilers are unmarked per wiki policy.
- Abner the pig eating a slice of (pork) bacon. Mr Hyunh's reaction is the icing on the cake.Mr. Hyunh: A pig eating bacon? That's very creepy!
- While making the title card for the video, Harold spells Arnold's name wrong. The video proper shows the kids noticed and had to cover it up (poorly).
- As the video ends, Harold and Stinky moon the camera, forcing Sid to quickly cover their behinds with the "The End" sign.
- Harold gives us some self-aware meta humor by stating "I was a one-dimensional bully until Arnold showed me my sensitive side."
- During the video, Eugene lists off everything Arnold has done for him, then gets attacked by a pigeon. As everyone laughs, it cuts to him with an eyepatch, several bandages, and a missing tooth as he says "I'm okay" on screen.
- Gerald casually talking about Helga's Stalker with a Crush habits — as all of that B-Roll in the video was from her personal collection.
- Helga claims it's all from security cameras. Gerald doesn't buy it for a second, considering everything is perfectly organized.
- When Gerald gets to the videos of Arnold's bedroom, Helga suddenly closes the laptop and tries to handwave it. Gerald also changes the topic not before saying "Major creep factor aside..."
- While Helga gives her typical excuse of doing it so Arnold won't be moping all summer, Gerald and Phoebe exchange a smirk.
- Mr. Simmons assures Arnold's grandparents that he will have everything under control during the trip and no one will get lost.Grandpa Phil: Hmmm, have you ever traveled with a dozen kids before? (Mr. Simmons gets an Oh, Crap! look)
- The fact that this has happened before. Mr. Simmons' class went on a field trip to a chocolate factory, but they had to leave early because Chocolate Boy snuck along for the ride — and Helga and Harold got left behind.
- Funnier if you interpret that as Phil knowing that Arnold and his friends will do something to get themselves in trouble, just like they usually do.
- Or both. Both is most definitely an option here.
- During the big fight, when a goon is about to attack Sid, Grandpa Phil suddenly steps out of a bathroom stall and unknowingly knocks the thug out with the stall door.Grandpa Phil: (to Sid) Don't go in there for a while.
- Rhonda's Freak Out over her hair which somehow turned into a disaster on the trip over. Nadine calmly watching and waiting for her to wind down makes it funnier.
- Things eventually get worse for Rhonda, where in the big fight at the prison camp, most of her hair gets chopped off after she barely dodges a goon's sword slash.
- Grandpa's list of possible diseases that Arnold could catch in the jungle, including the ridiculous possibilities of catching "elphantitis", "leprosy", "tennis elbow", or "athlete's foot".
- Grandma dementedly driving the stair truck that Grandpa is standing on while still talking to Arnold.
- Eugene trying a fruit he's never had before, and immediately swelling into a human balloon because he's Eugene. He spends the rest of the movie this way. (Funnily enough, this seems to actually protect him rather well from the rest of the craziness that occurs during the trip.)
- Rhonda being scared of the bugs around. Nadine, though...Nadine: This is like Christmas.
- After being shipwrecked, Eduardo gives everyone the good news that there's a habitat where they'll be safe. That's about the only good news he has.Eugene: Is the habitat a short walk from here?
Eduardo: Oh no. No it's many, many, many miles. Over rough trails.
Rhonda: Oh, that is such bad news.
Eduardo: Through steep, muddy jungle.
Rhonda: Just got worse.
Eduardo: But then it smooths out.
Students: (Gasps hopefully)
Eduardo: And becomes an enormous swamp.
Students: (Groan in disappointment)
- After the boat is scuttled, Harold gets hungry and starts to complain, causing Rhonda to remember that she had some extra food packed in one of her other suitcases she had to leave behind. She only makes it a few steps to go back for it before the boat suddenly explodes.
- Eduardo tells the stranded students to take only what they need. Curly responds by immediately ripping off all his clothes and switching to the tribal attire he had on underneath.
- Lasombra's big reveal that he's been posing as Eduardo this whole time. When Arnold acts wounded by the betrayal, Lasombra mocks him.
- Rhonda ignores the whole being kidnapped by pirates thing to ask the hard-hitting question of our time.
- Curly offers to turn traitor and be the camp snitch for Lasombra.Lasombra: Sorry kid. You are too loco even for us villains.
- When Brainy sees Helga tear her Arnold locket apart on the ship, he gets the message and jumps off of it.
- Doubles as a heartwarming moment when Brainy gives Helga her repaired locket, after she'd thrown it in the river and torn up the picture of Arnold inside. Helga responds by kissing him on the lips. The moment goes from heartwarming to hilarious when Brainy pulls a pan flute from out of nowhere and begins playing it and dancing madly.
- Harold takes out his anger at Arnold on an Arnold-shaped punching bag. A short while later he's hugging it and bawling his eyes out, "I miss Arnold!"
- Phoebe hacks Rhonda's cell phone to send an SOS to Big Bob's beepers. Bob has no clue what it's about, until Miriam remembers the girls are on a class trip. They immediately scream out "OLGA!" and rush to the car. It's only after they drive off screen that they remember Helga.Miriam: Oh! And the other one!
Bob: Oh right, right, Helga.
- Grandpa and Grandma find out that Arnold is in danger by Abner traveling all the way from Central America and stowing away on a plane to the United States. He tells the story to Grandma in oinks, who, can understand him perfectly. She only gets distracted during the story when she finds out there's shrimp cocktail in first class.
- Just the fact that Abner and the snake that followed him are given their own seat on the plane, with Abner staying in first class and the snake staying in the economy class.
- Some Black Comedy during the middle of Lasombra using his men to test the booby traps leading the Green Eyes hidden city, where he has a brief back-and-forth with one mook in particular.Lasombra: Please, you first.
Mook: No, Jefe. You first.
Lasombra: No, no, no, I insist. (takes out sword) You first.
Mook: (goes first and falls to his death) I shouldn't have gone fiiiiiiiiirst!
- Arnold, Helga and Gerald find the shrine the Green Eyes have of Arnold. Helga says she's seen better.
- Mr. Simmons going crazy and trying to teach a class full of monkeys. Behind him are four signs that say "Please Don't Hurt Me".
- What's Curly's role in the escape plan? Freeing the animals.
- As part of Phoebe's plan, Sid and Harold have to create a distraction for the guards. How do they do this? They jump on the platform in the middle of the base and dance around like idiots, with Sid playing air guitar and Harold yelling "Look at me. I'm a distraction!"
- As the prison escape reaches its climax with Arnold's grandparents and Helga and Olga's parents arriving in the nick of time, Olga gets the perfect revenge on the pirate she had previously fallen for: by siccing Daddy on him!Olga: Oh, Daddy, that boy was mean to me!
(Big Bob goes Papa Wolf on Che)
Big Bob: (Angrily chasing Che) YOU AND ME ARE GONNA GO ROUND AND ROUND!
- Before that, Olga suddenly sounds hammy after they were imprisoned by Lasombra. It doesn't help that Nika Futterman's delivery of her lines made Olga go from Miss Perfect to MISS LARGE HAM.
- After it's revealed the real Eduardo was the one who rescued Arnold, Gerald, and Helga from falling to their deaths from the broken rope bridge:Helga: Wait! Not another Eduardo! "Your parents' trusted friend with a mustache?" Ha! I've heard that before! Why should we trust him?
Eduardo: You are welcome to climb back down.
- A small one but when Arnold is trying to activate the Green Eye's machine with Helga's locket, he keeps struggling with it until Helga takes over and turns it on while calling Arnold "Football Head" in a tone of disgust.
- Grandma sincerely asking at the end of the movie, "Who is that cute, blonde boy?"
- There's always the Running Gag of animals running out of Arnold's home after he opens the door to leave. It's always the typical cats, dogs, and Abner the pig. At the beginning of the movie, a bat is included among the animals running out, and by the end of the movie, it now features a monkey, a butterfly, a parrot Stinky befriended and the snake that followed Abner home.
- Big Bob is still stubbornly trying to sell beepers and pagers even though every other character is shown using a smartphone.
- There's something really funny about Helga telling Bob his beepers are no longer in style and that it's a new era, despite only a year having passed since the original series where beepers were popular.
- After all the craziness the class has been through, when they are seen returning to school, you can hear Mr. Simmons sounding quite astonished when he announces that, somehow, he still has a job.
- While a mixture of comedy and Tear Jerker, the fact that Miles and Stella seem to be so unadjusted after being gone for a decade is amusing.
- Further on that mix of laughs and tears, you laugh when you see Arnold's parents walk him to school and be so close to him to the point of My Beloved Smother, then a tear falls when you remember that this is the first time they get to be parents and actually walk their son to school, make him breakfast, or just be around him. Arnold thinks nothing weird of it and is perfectly happy!