Audio problem: In the last scene before the credits, Napoleon and Deb are playing the ball game, and when they high-five each other at the end, it is out of sync.
Continuity mistake: When Napoleon is counting up his money, his watch moves further up his wrist between shots.
Deliberate mistake: When Napoleon asks the school secretary if he can borrow the phone, she pushes the phone toward him but in the shot of Napoleon you can see the phone never actually moved from before he asks to borrow it to the time he makes the call. This is only seen on the full-screen version of the film. The phone is not visible on the wide-screen version because the bottom portion of the image is cut. (00:07:00)
Continuity mistake: When Deb gives Napoleon the picture of the girl, the position of the picture in Napoleon's hand changes between shots.
Continuity mistake: When Kip runs over the plastic bowl to demonstrate its strength, watch the location of the left rear tire's valve stem. In the close-up when Kip wedges the bowl behind the tire, the valve stem can be seen near the top of the screen at the 4:00 position. When Kip walks to the front, but the van hasn't moved yet, the valve stem is now at the 7:00 position.
Continuity mistake: When Napoleon is giving Trisha's mom the dance invitation you can see a car in the reflection on the door. Then when it shows the door again the car is gone.