When the gang all decide that they are going to "moon" Principal Wartz, Arnold thinks that it's a bad idea, but ends up inadvertently getting caught and taking the blame./Olga comes to PS 118 to be a student teacher.
Full Moon: Harold, Sid and Stinky 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.
