Continuity mistake: When Marty is up on the roof with Jason after being busted as a liar, he looks down at Marcus Duncan standing in front of eight live feed monitors, but in Duncan's close-up there are fourteen monitors. The entire top row of monitors is gone in the wideshots. (01:17:55)
Continuity mistake: After Marty leaves the birthday party and asks Monty to reschedule with Marcus Duncan, when his car's radio starts blaring Marty's wearing his seatbelt in the shot facing him, but in the next side shot as he tries to turn off the radio Marty's seatbelt is instantly off. (00:47:35)