Continuity mistake: When John Cusack is getting ready for his date with Daphne Zuniga, he unzips his trousers to tuck in his shirt twice.
Continuity mistake: When John Cusack is in the bar buying the other guys drinks, his stationary beer on the counter changes positions several times. Half the time the handle of his mug is facing away from him and the other half it is to the side.
Continuity mistake: When John Cusack is sitting dejected after he jumped into the pool and Daphne Zuniga comes down the stairs, the bangs of his wet hair change position three times from the wide shot to the close-up, to the next medium shot. (00:13:15)
Continuity mistake: When Gib passes out on the bed after juggling beer cans, Allison covers him with a blanket. There is nothing else on the bed. After we cut back from a close-up, an empty beer can has appeared out of nowhere and is resting by his leg.
Audio problem: As Tim Robbins drives off at the start of the trip to California, he sings "The Age of Aquarius," but his lips through the car window aren't mouthing anything close to the line he is singing. (00:28:10)
Continuity mistake: When Daphne Zuniga exits the locker room and walks towards the pool, she reaches a doorway in the wide shot. Then when they cut to a medium shot she takes three steps before she reaches the same doorway. Then when they cut back for her next reaction shot, she takes another two steps before reaching the same doorway yet again. (00:11:20)
Continuity mistake: When Gib offers Allison pork rinds, there are two prop bags, one with a big rip and one without. The bags switch back and forth depending on the cut throughout the scene.
Continuity mistake: When Gib is teaching Allison to shotgun a beer, she spills it on the left knee of his sweatpants. When he gets up to clean off, his sweatpants are soaked on the thigh and crotch and his knee is dry. When he walks outside a minute later, his pants are completely dry.
Factual error: When John Cusack is talking to Daphne Zuniga in the swimming pool, watch for the view of the window. There is a palm tree growing at this Northeastern, snow covered college campus. (Obviously an oversight when filming in California, but a mistake nonetheless.)