Before Matt and Tori get on the trampoline, Matt sets down the bottle of wine and it falls over. When they both get off the trampoline, the bottle can be seen upright on the ground.
In the video store scene at the beginning, as Matt is about to re-enter as a customer, there are two woman walking past. One is wearing jeans, a purple top and holding a red purse, the other is wearing khaki pants and a pink top. They walk by before Matt enters and disappear from the frame. They walk by a second time as he enters the store.
When Matt and Barry are found in the stolen car (after they run it off the road while trying to snort cocaine) by Matt's father and his police partner, Matt's father breaks the driver's side mirror off the car with his baton. When he lifts Matt off the ground, the mirror is on the ground, but there is what appears to be one still attached to the driver's side of the car; it is actually the head-restraint of the driver's seat that the camera angle makes appear to be a reattached mirror.
Matt is seen taking multiple sips of his drink at the beginning of the party, but the bottle looks full in multiple shots.
When Anna first informs Matt that she heard back from Cambridge in her room she does so by holding up an envelope that clearly says "Cambridge University" on it with the university's crest below.
The correct name is "University of Cambridge" and would say so on the envelope (with the crest to the left) like this:
XX University of
XX Cambridge
Besides, she would not receive her notice from the University of Cambridge anyway because you apply to a college within the university and the college responds.
Barry states that the Mercedes he stole has the "Corinthian Leather package." "Corinthian Leather" was a marketing term used by Chrysler and wouldn't have been available in a Mercedes.
In the 1984 yearbook, there are several anachronisms. There's a clip of A-ha's video for "Take On Me", which wasn't released until 1985. There's a photo of ALF, a video clip of the California raisins, and a photo of four girls with the inscription "walk like an Egyptian". Alf, the California Raisins and the song "Walk Like an Egyptian" are all from 1986. Near the end of the yearbook credits, the phrase "don't worry, be happy" appears with a yellow happy face. "Don't Worry, Be Happy", the Bobby McFerrin song that popularized the phrase, wasn't released until 1988.
The song Safety Dance is played at the party, which happens in 1988. The version that is played was the Biomix version from the 1996 movie Bio-Dome, not the 1983 album release.
There is a scene where Motley Crue's "Kickstart My Heart" is playing prominently, but the album came out in September 1989. The film takes place on a night in 1988.
In the beginning of the film when they are at Suncoast Video, the VHS box for the film "Twins" appears on a wall behind Topher Grace. This film takes place in early September 1988 and "Twins" wasn't released theatrically until December 1988. The EARLIEST "Twins" would have been released on home video is summer 1989.
While the film is set in 1988, some of the films seen at the video store would not see a video release until later on.
When Barry gets fired, he runs to Mike's sister's car and gets in. As the car passes the cameraman can be seen in the window.
"Japanese takeovers' is the initial lie Matt Franklin tells Tori regarding his job description at a non-existent Goldman Sachs Los Angeles office. When Matt introduces himself at the second party in Beverly Hills to Tori's lecherous boss at Drexel Burnham Pete, his story changes to 'currency speculation'. The supposedly intelligent Tori accepts this new lie with out blinking an eye and even confesses she was impressed with Matt's 'Rainman-like' gift with numbers demonstration.
When Matt Franklin is giving his speech before entering the ball, he can be seen in the crowd with Tory Frederking at the same time.