List of Hey Arnold! episodes

This is a complete list of episodes for the animated television series Hey Arnold, which originally aired on Nickelodeon from October 7, 1996 to June 8, 2004. The series aired in reruns on Nickelodeon until 2007. Reruns have been broadcast since 2011 on Nickelodeon's sister network TeenNick during the channel's late-night television block The 90's Are All That, and still rerun on the block's re-brand, The Splat. There are 100 episodes in total.

Arnold accidentally knocks Harold out during a baseball game, and the bully gives Arnold 24 hours to live before he beats him to a pulp.

Save the Tree: Arnold and the gang must stop Big Bob from chopping down the oldest tree in town.
New Teacher: When the kids make their new teacher, Mr. Simmons, quit his job, the replacement makes them realize what they lost.

Longest Monday: Schoolyard tradition has it that on the first Monday of June each year, the fifth graders throw the fourth graders into trash cans. So, Arnold and Gerald try to make a run for it. As more people are thrown into trash cans and the fifth graders know all the routes, Arnold and Gerald find out eluding the fifth graders is harder that they thought.
Eugene's Pet: After Arnold accidentally kills Eugene's fish with a yo-yo, he must do something to make up for it.

Phoebe Takes the Fall: Helga demands that Phoebe lose a quiz competition to impress her competitive father.
The Pig War: Arnold, Grandpa, and friends reenact the Pig War.

Crabby Author: Arnold does his school report on an author he likes, only to find out that she's a grumpy, old hag.
Rich Kid: Lorenzo, a neurotic rich kid, comes to P.S. 118. All the kids try to help him become an average kid.

After hearing that Arnold is Romeo in the school play of Romeo and Juliet, Helga does everything she can to get the part of Juliet and kiss him.

Full Moon: Harold, Sid, and Stinky all moon Principal Wartz, but Arnold is blamed, even though he was just an innocent bystander.
Student Teacher: Helga's sister Olga comes home for spring break and becomes a classroom aid in Helga's class, much to Helga's chagrin.

Parents Day: Arnold asks Grandpa Phil 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.

The Journal: 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. Note: Last episode produced; originally designed as a cliffhanger as a lead-in to "The Jungle Movie", a theatrical feature that was cancelled and years later revived as a two-part television movie.

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