Continuity mistake: When Donnie steals Chuckie's clothes and glasses, Chuckie puts on Donnie's shorts and complains about his eyesight. But later in the movie, when he doesn't have his glasses, it seems he can see just fine. Then, when he gets his glasses back, he says something like "I can see again."
Continuity mistake: When Donnie takes Chuckie's clothes and then throws Chuckie his own shorts, Chuckie puts them on and the shorts fall right off. Chuckie makes a comment about his shorts being a lot bigger, yet Chuckie's shorts seem to fit Donnie perfectly and a few minutes later Donnie's shorts now fit Chuckie just fine.