Continuity: Gerald's doctor's name is spelled "Murray Stieglitz" on the sign, but "Steiglitz" in the credits.

Continuity: In the locker room, Sid's hair goes from stringy to full and back to stringy.

Audio problem: In the comic book shop, Gerald says "Ho. Touche, sir." but his mouth doesn't move at all.

Plot hole: Mr. Simmons asked that each student put their name on the test folders, but the folders already had names on them when he handed them out.

Revealing: The test paper Eugene put back in Harold's folder is blank.

Plot hole: When Eugene dropped the tests, just about all of them fell out of their folders, but apparently only Harold and Helga's were switched.

Continuity: In "Oscar Gets a Job", Oscar goes around asking people for money. When he talks to Ernie, you can see that there is a phone and a light to the right of the door. When Arnold confronts Oscar in the hall, you can see Ernie's room (7). The phone has disappeared.

Continuity: There are more than 16 slips in the hat, but only 16 students in class, and only 12 hands went in to pull out slips.

Other: In the scene where Arnold meets the gang in the alley way, they give ideas to crash Rhonda's party. When Curly tells his idea to go to the zoo and free all the animals and there are shots of the gang looking at him confused,in two of the scenes, you'll notice that when Stinky and someone else looks at him, the background is at the school, not the alley.

Continuity: When Joey is shown in close-up, his missing tooth looks like it's there but it's covered with something black and his missing tooth keeps reappearing and disappearing in the last scenes.

Continuity: Grandpa's rubber raft got much bigger between the time he left the greenhouse and the time he arrived.

Continuity: Besides the fact that when Helga is sharpening her pencil, the desk arrangement changes, one of the students visible when she looks at Arnold is...Helga.