Continuity mistake: When Freddy is talking to Eddie about going to play pool, his knapsack strap goes from hanging off his shoulder in one shot to being on his shoulder in the next.
Factual error: In one scene Fred Tate is explaining to his mom, Dede, what a 'lepton' is. He says first "A lepton is a Z-particle", then furthermore says "Do you know what protons and electrons are? [...] Well leptons are even smaller." In fact, electrons *are* a kind of lepton. Also, there is only one Z-particle, and it is quite different from leptons.
Continuity mistake: In the shots of Tate in the college classroom, notice the young man in the green shirt seated to his left - two different extras fill the slot in various scenes (both happen to be friends of this contributor's sister).