Continuity mistake: When Spinelli is challenging the hustler kid, she asks for Gretchen's bow (for a blindfold). In the shots after that, Spinelli is still blindfolded with Gretchen's bow, yet Gretchen is still wearing it.
Other mistake: When the Ashleys are playing jacks, Ashley B is wearing her usual yellow sweater, but in the next shot, it becomes red, the wrong colour. It goes back to yellow in the next shot.
Other mistake: After Dave takes away Mikey's lunch tray, it fades to a shot of the school clock, and there is no 5 on it.
Factual error: After Digger Dave and Digger Sam split up, they show that Sam was unfocused and was digging everywhere. Even through concrete?
Continuity mistake: After it is explained that without Dave, Sam is unfocused, you see that he has dug holes just about everywhere. However, after that scene, all the holes disappear.
Schoolworld - S4-E21
Continuity mistake: When Gus gets locked out of the school after recess, he asks SAL to open the hallway door. He looks up at the clock, and the time on it is 10.46.05 (then goes up to 10.46.08 by the end of the shot). A few seconds later, the time changes to 18.46.16, then 10.46.17, then 10.45.18.
Factual error: When Menlo is hoppin' scotch, he lands on 10 with both feet, and 10 is a single square.
Suggested correction: He does, but this is simply a mistake Menlo makes as a character. And it is not a 'character mistake'; I can see many people making a very simple mistake like this while playing hopscotch. I know I probably have as a kid. Also, he lands on an 8 square, not a 10 square.
Audio problem: When Randall says, "Way to hop, man." his mouth doesn't move when he says 'man' until after he's finished saying it.
Continuity mistake: When Randall begs Gretchen to do his homework, Mikey says, "Tutoring is just another word for helping," and his backpack is green. A few seconds later, it changes to blue.
Spinelli's Masterpiece - S4-E27
Continuity mistake: When the kids are all on the jungle gym to see Spinelli's drawing, Jerome can be seen sitting on the bar of the swings. However, when everyone is cheering he has suddenly moved to the ladder.
Spinelli's Masterpiece - S4-E27
Revealing mistake: When the hosepipe bursts and Spinelli's picture gets ruined, the water rises up a few inches off the ground, but the school has a chained fence so the water should run out.
Bonky Fever - S4-E30
Continuity mistake: When Mikey asks the lunch lady for more pudding for Bonky and she refuses, Mikey falls down on his back and starts throwing a tantrum. A second later, he has turned 90°.
The Secret Life of Grotke - S4-E32
Plot hole: In the scene where T.J. and his pals are trying to find the password to the building, they are using a cup telephone. When the man talks, they can hear him, but when the kids talk, the men on the other side can't hear them.
The Secret Life of Grotke - S4-E32
Continuity mistake: When the gang are sat at the table before Miss Grotke comes on, the table is empty, but when Miss Grotke comes on stage, they suddenly have drinks.
Continuity mistake: In the beginning, Gretchen says she's short on money, so she can't get a chocolate milk, just a white milk. But, when T.J. walks by with his food, Gretchen has a chocolate milk, such is evident from the brown carton.
Suggested correction: Gretchen tells the lunch lady that because she is one penny short, she will swap the chocolate milk (in her hand) for a regular. She puts the milk on her tray and walks off screen. Then, when T.J. walks past her, the camera pans over to Gretchen watching T.J. with that same chocolate milk on her tray she is holding. Gretchen got distracted by T.J.'s encounter with the lunch lady and stopped to watch him, but she was still going to swap the chocolate milk for a regular later on.
Chez Vince - S4-E41
Continuity mistake: In the cafeteria, TJ is wearing a suit to welcome the customers. But when he and the rest of the guys go to the teacher's lounge he's back in his normal clothes.
Continuity mistake: Gretchen starts talking to that man who doesn't talk, but later when Mikey is singing for the first time, you see that man booing him, then a minute later Gretchen is still talking to him.
Some Friend - S4-E44
Plot hole: They say in this episode that Menlo was always an organized freak. But in "Principal for a Day" it turns out that he was a hyper-major kid until he started working in the school office.
