Continuity mistake: When Clifford is running down the hallway from Moody and his gang, Moody closes in on him by almost 40 feet. In the following shot, outside the auditorium, Clifford is a greater distance from the gang, sighing relief at the apparent getaway. Unless he suddenly picked up speed rounding some hallway corner, the time distance is impossible.
Continuity mistake: Near the beginning of the film, Bill Murray takes a seat front-row-center in court. Moments later, he's doing push-ups in the corridor. A few moments later, he's back in the same seat front-row-center in the courtroom.
Continuity mistake: When Ira and Glenda are discussing Nick, who is hiding under the bed, Ira briefly stands on Nicks right-hand pinky finger. After Ira has walked away, under the bed Nick grimaces while holding his left-hand pinky finger.
Continuity mistake: When Mickey gets into the '57 Chevy to "test drive" it, there is no gear shift lever on the steering column. The camera then shows him buckling his seat belt, and when it returns to the previous angle, there is that missing shift lever.
Continuity mistake: Peppermint Patty can be seen in the same class as Charlie Brown and Linus, even though she says that her school has chosen her as a Foreign Exchange Student and is apparently unaware that Charlie Brown has been given the same honor.
Suggested correction: Peppermint Patty lives on the other side of town from Charlie Brown and Linus in America, so she does not attend the same school.