Other mistake: When 1 strikes off 2 (I think) from the calendar we can see that 1 is Wednesday, 2 is Thursday, 3 is Friday and that 4 is Saturday but 5 is Monday; meaning that Sunday has no date.
Other mistake: In the end credits, BASSES is misspelled as BASESS. (01:45:10)
Other mistake: After Precious has her baby, Abdul, her school friends visit her in the hospital as her nurse, "John," is eating lunch with her. When John introduces himself to Precious' friends, he says he is a nurse's aide, and then later refers to himself as "Nurse John." When he stands up to leave the hospital room, you can see the word "NURSE" on his hospital ID badge pinned to his scrubs.