Audio problem: When Corny introduces himself at the auto show, the audio is not in sync with his lips.
Continuity mistake: At the end when Michael Jackson is singing come together, at the end of the song his shirt is undone, but when the camera shoots back on him his shirt isn't ripped.
Factual error: Buster Franklin's bass player is playing a MusicMan StingRay bass, even though they didn't appear on the market until 1976. The guitar isn't from the fifties either, but I can't make out what it is. (02:12:30 - 02:14:50)
Continuity mistake: In the scene where Ken is picking Rita up from school her bookbag is red with 2 triangles on it as they go around the school, after Rita gets on, her bookbag then turns blue with no triangles.
Continuity mistake: In life number 3, Uncle Todd wipes the blue paint ring from Garfield's face and then places him upon a pink dotted mushroom near two paint cans. But between shots, both paint cans disappear. (00:13:50)
Other mistake: Mr. Phillips told Michael (Danny) that he'd like to hear him play on his "Steinway at home", but didn't say when or give Michael his address, but Michael was able to ride his bike to the Phillips' house. Michael was in this new school (and State) for only one day, so it seems unlikely that he'd know where Mr. Phillips lived. (00:26:33)