Continuity mistake: When O'Bannion gets paint dropped on him, it falls only on the left side of his head and body, but as he walks away he is covered in it.
Audio problem: In the scene where O'Bannion and Benny are hazing Hershfelder, Don goes for a beer in the trunk of O'Bannion's Duster. You hear a clicking sound as Don opens the trunk but in that shot he only lifts the trunk lid without using keys or having his hands anywhere near the lock.
Continuity mistake: After the paint's poured on O'Bannion, he pushes Mitch and puts his hand on his car as he opens the door, but he leaves no paint on it.
Plot hole: Where are all the graduating students? The ones that are going to be seniors the next fall are established. But what about the ones who graduated? There is absolutely no sign of any one of them anywhere, not at the Emporium, that at the outdoor party, nowhere.
Factual error: The Coke sign in the background when Donny goes to steal the beer and Mitch is the lookout was introduced in 1987.
Audio problem: When the girl is playing the guitar and singing at the party, her hands on the guitar strings are not in sync with what we hear playing.
Factual error: Benny's Black Chevrolet truck has a 90's-era GM factory steering wheel, probably from a later restoration.
Continuity mistake: In the scene where the seniors are at the baseball game waiting for Mitch, Pink is stopped by an older man who asks him if "this arm is ready", for football. It is clear that the man grabs his left arm when asking him. But later in the movie, when they are on the football field, Pink throws the no drug use form and it is clear that he throws with his right arm.
Continuity mistake: After Carl's mom pulls a shotgun on O'Bannion, his paddle is showing the "F AH Q" side. In the next shot, it is reversed showing the "Badass" side.
Continuity mistake: In the scene when they are initiating the freshmen girls, one of the freshmen is taken over to Dawson and she is told to propose to him. When she says, "Anything you want." she is kneeling. Then it shows Dawson telling her to make an O with her lips and when it goes back to her doing that she is sitting on the ground.
Continuity mistake: In the scene in which Matthew McConaughey is wearing a frilled lace mock polyester shirt, while offering his profound theory upon living, you can see the bulge of cigarettes, in his upper left pocket, a moment later, they're gone.. then when the camera angle reappears on him, they're back.