Audio problem: When singing Reproduction, a boy sings "Oh I think I'm gonna throw up"; yet he sticks his finger down his throat and keeps it there until the line is over, never closing his mouth; how did he make the 'p' sound on 'up' without closing his lips together? The words are pronounced very clearly and the camera doesn't cut from his face until after the line is done.
Audio problem: When Russ Thorn is walking towards Linda in the high school hall, you can hear Linda's scream before she visibly screams. (00:12:45)
Audio problem: In the scene where Jack Brown (Richard Pryor) is talking to Eric about "Earning a friend" there is a problem with the lip-sync when the camera changes to an overshoulder of Richard. His mouth is moving but the spoken text is different. This occurs repeatedly during that scene.
Audio problem: When people are getting on and off the elevator to that loud music, the music stops before the elevator closes.
Audio problem: After Spicoli crashes Jefferson's car, Jefferson's brother says "My brother's gonna kill us - he's gonna kill us" yet his mouth isn't moving during those lines (even though shown from the back you can still tell). Then camera faces him and he now matches the words.