When Arnold has a daydream while playing baseball, Harold tells him he has 24 hours left to live (this pilot was re-made into the episode called "24 Hours to Live")

Harold, Sid, and Stinky all moon Principal Wartz, but Arnold is blamed, even though he was just an innocent bystander.

Helga's sister Olga comes home for spring break and becomes a classroom aid in Helga's class, much to Helga's chagrin.

After Sid works off a debt with loan shark Big Gino, the two become friends, but when Sid is told to give Arnold a swirlie, he has to choose between the two.

Gerald's older brother Jamie O has a sudden burst of kindness when he finds a girlfriend, but Arnold and Gerald soon find out that the girl is just using Jamie O.

After losing Eugene's birthday party invitations, Arnold feels obliged to throw him another party, but it doesn't work out.

Stinky grows a huge pumpkin to enter in a city competition.

After Bob pops his spine, Miriam runs Big Bob's Beepers. She gets in over her head and forgets about her family.

Arnold finds out that Oskar is illiterate and tries to teach him to read.

Helga wants to show Arnold that she can be as sophisticated as Lila is by taking him, Gerald, and Phoebe out to dinner with a coupon she won. She devises a plan to get out of paying when she discovers they're at the wrong restaurant.

Phoebe is promoted to the sixth grade, but realizes that her new so-called "friends" are just using her to do their homework.

A sleep-talking Helga confides into Bob's parrot about her love for Arnold. The next day, the parrot flies into Arnold's window, and it is up to Helga to get it.

Crisis strikes when Gerald's little sister, Timberly, eats a stock of chocolate turtles that he and Arnold are supposed to sell for a local scout organization.

Helga tries to separate Arnold from Lila while at the annual Cheese Fair.

Harold, after discovering his friends think he is obese, decides to go on a weight-loss cruise. When he comes back, though, he is noticeably larger.

After Grandpa tells Arnold that he never got his grade school diploma, Arnold convinces him to come to go back to school at P.S. 118.

Arnold and Helga must care for an egg for a school project about parenting. Meanwhile, Rhonda and Harold are project partners and must also take care of an egg.

Helga becomes a model, but she quits after she gets irritated at everyone dressing like her.

Arnold's classmates are tired of constantly telling them the right thing to do, so he stops giving them advice. Nevertheless, when his classmates get into sticky situations, they are in desperate need of his advice.

After getting in a car accident, Bob and Grandpa face off on the golf green, with the loser having to pay for the damage to both cars.

Rhonda attends a finishing school, but is far from impressive with her stroppy attitude, and seeks help from fellow student Big Patty.

Arnold's bland country cousin, Arnie, comes to visit. Arnold begins to notice that Arnie and Lila show interest in each other, making him jealous.

Oskar has to take care of his infant cousin-in-law (also named Oskar), while both Susie and her cousin are gone.

Phil's twin sister comes for a visit, bringing along an unsettled conflict between them.

Arnold and the gang are part of a synchronized swimming team led by Coach Wittenburg.

After eating pork rinds, Helga sleepwalks, uttering her secret about Arnold as she does so.

Arnold, Grandpa, Grandma, Ernie, and Mr. Hyunh compete on a game show against a "perfect" family from PS 119

Arnold tells an urban legend about a decapitated taxi driver. The gang goes out, only to find the details in the story are becoming real.

Arnold and Gerald try to prove superstitions are fictitious, only for it all to backfire on them.

Arnold's Grandpa recalls his adventures as a soldier in the Second World War, outwitting a regiment of Nazis, while Gerald's dad, Martin, remembers his own time serving in Vietnam.

Helga confides in the school psychiatrist about her social life, family life, and her love for Arnold.

Dino Spumoni is found missing and then declared dead after what appears to be a suicide attempt. but Arnold finds out that this isn't the case, and he secretly lives in the boarding house, believing that his work will skyrocket in value after his "death".

Helga inscribes her name in her Arnold locket.

Harold is suspended and will do anything to get back into school.

When Arnold gives the superhero Monkeyman a taste of normal life, he's far too busy to bother helping the weak and downtrodden.

Helga and Harold must return to town on their own after the bus leaves them behind after a school trip to a chocolate factory, and Helga has tickets for a wrestling match and she can't be late.

Helga decides to act like Lila so Arnold will like her..

Mr. Green runs for city council.

Sid thinks Stinky is a vampire.

Olga gets into a "Big Sis" program, but her "Lil' Sis" is Lila.

Arnold, Sid and Gerald find a bag filled with money, but when Arnold loses it, everyone thinks he stole it.

When Mr. Simmons is upset that Principal Wartz is being too strict with the students, Wartz decides to resign and he selects Mr. Simmons to take his place. The newly promoted Principal Simmons decides to make massive reforms to permit the school environment to be more liberal, though will the students at P.S. 118 appreciate his authority?

The kids must face two bullies when a new kid, Ludwig, returns and wants the vacant lot for himself.

When Phoebe breaks a leg after being hit by a truck, Helga believes it's her fault (and it is), so she starts being nice to Phoebe. Yet when Phoebe's leg heals, she decides to stay disabled for a little longer.

Sid becomes obsessed with cleanliness.

Ernie starts dating a tall model, but she doesn't want to continue dating him because of his height.

Arnold asks Grandpa what really happened with his parents, and he finds out that they disappeared after they left the country on a plane, although they might still be alive.

When Arnold, the boarders and the Patakis go to the beach, a girl uses Arnold to win a sandcastle competition. Ernie gets buried in the sand. Miriam and Suzie start taking dancing lessons. Grandpa thinks he's stuck on an island. Oscar starts using a metal detector to find ""treasure."" Big Bob gets a bad sunburn. Helga tries to warn Arnold that he's just being used.

Arnold gets stuck in a tree with Harold and Eugene.

Rhonda's family goes broke and they move into the boarding house.

Helga gets amnesia, and Arnold starts acting nice to her.

Grandpa Phil and his old friend have been feuding for quite some time, as their friendship fell apart years ago. However, they still attempt to compete with one another as they each believe they are the better individual; though when both men decide to enter the extremely dangerous Old Iron Man triathlon, Arnold attempts to put an end to their feud, as he does not believe they should risk their lives over something so trivial.

Arnold visits his cousin Arnie, whose friends look remarkably familiar to Anrold's

Chocolate Boy wants to give up chocolate.

P.S. 118 is having an Arm Wrestling contest, but Harold get humiliated when he loses to Patty before the contest, so he asks Patty for some pointers on winning.

After Arnold saves the life of a rich man, the man invites Arnold and Grandpa Phil to his house. He tells Arnold that he wishes Arnold was the son he never had, but he really does have a son, but they share nothing in common.

Arnold is sick and tired of everybody preforming their April Fool jokes on him (escpecially Helga), so he tries one of his own, but it backfires when it temporarily blinds Helga.

Gerald is involved with his new favorite game which Arnold dislikes.

Arnold, Gerald, Harold, Sid and Eugene go on a fishing trip with their fathers and Phil.

Rhonda uses a folding paper fortune teller to see who will marry who, and Arnold and Helga get paired up, causing them to both dream what life would be like married to each other.

Stinky, Harold, and Sid are on the run after they think they blew up a police station.

Mr. Hyunh has Arnold pretending to be his son for his new employer.

Mr. Hyunh, Oskar, and Ernie purchase a race horse, or so they think.

Curly gets Rhonda to act like his girlfriend after something happens to Rhonda's mother's fur coat and he fixes it.

Arnold finds a journal describing the adventures of his parents in the Jungle. Also, it contains a map telling where they had to go after they left him.

Arnold finds a journal describing the adventures of his parents in the Jungle. Also, it contains a map telling where they had to go after they left him.

Arnold does something for Timberly, causing Timberly to have a crush on Arnold. She makes Lila start to like Arnold because he has been helping Timberly.

Eugene gets the lead role in the school musical "Eugene, Eugene". But the play director cuts the parts that Eugene is a hero, and makes the parts look like he is a loser.

Gerald's Ghost Bride story inspires the other boys to venture into the cemetery at night, but they may have bit off more than they could chew, because they're hunted down by two different Ghost Brides.

Gerald gets jealous because he thinks Jamie O. is trying to steal the girl he likes, when, actually, the girl likes Jamie O.

After Mr. Simmons wins an award, a TV station does a documentary on how he teaches.

After Big Bob has a heart attack, he tries to become nicer.

Phoebe gets embarrassed after she "passes gas" in front of a microphone.

Grandpa's Packard is stolen from an antique car show.