Continuity mistake: In the scene where Will tells Vivian and Phil that Carlton is in Compton, Vivian takes off her earring from her right ear. A few shots of Will pass and when she goes to take off her other earring, the left ear doesn't have one, and the earring is on the right ear again.
Continuity mistake: A member of the poetry club responds to Will's "You're a poet and you don't know it!" with a sassy "I -AM - a poet and I -DO - know it" in a close-up. In said close-up, she is holding her hand on a book, while in the shots before and after, her arm is in a different position. (00:06:30)
Continuity mistake: During the award dinner, when Hattie says the line about "Zeke sprung from the ground like a big ol eggplant," watch the table in the back, next to the door. The man sitting there wipes his mouth raising a napkin 3 times in 3 separate shots. (00:19:00)
Continuity mistake: When Will puts the last of his wall-shaking staples on the Malcolm X poster before the butler's interruption, the poster is almost perfectly flat. When Geoffrey walks to the poster, a bottom corner is noticeably raised. When Carlton walks to it, it's flat again, and raised when Will freaks out at the mirror. (00:07:40 - 00:10:00)