Plot hole: Early in the movie, the principal from Precious' school buzzes Mary's apartment intercom to talk to Precious about alternative education. In order to hear what the teacher is saying Precious has to press the 'Listen' button, but occasionally the teacher can be heard speaking through the intercom even when Precious isn't holding the listen button.
Precious (2009)
1 plot hole - chronological order
Directed by: Lee Daniels
Starring: Paula Patton, Mariah Carey, Mo'Nique, Gabourey Sidibe
Character mistake: Early in the film in the scene in which Precious is in math class just before being called to talk to the principal, on the blackboard someone, presumably the teacher, has written REQUIRMENT, which is a misspelling of "requirement"
Joann: Hi, I'm Joann, my favorite color is fluorescent beige. I'm already in the music business, shoot, I'm just here to get my GED.