Continuity mistake: In the scene at the mall around Christmas, Cassandra moves her necklace to the side, under her collar. But with each shot it changes from either in front or under her collar. This happens again at the end before Cassandra, Roland, Patrick and Mary go to prom.
Continuity mistake: In the part where Mary is in the pool and hits her head on the ladder, the carpenter jumps into the pool with his shoes on, but when he swims by with Mary you can see that he does not have shoes on.
Factual error: Right before the American Eagle students find the graffiti on their building, Mary and her friends comment that there is only one more week of school, setting the scene in spring. In the background, many of the trees have yellow leaves and are beginning to go bare, making it autumn.
Continuity mistake: In the restroom, after Cassandra finds out that Mary really is pregnant, she hugs her. In the wide shot, Mary's face is in another position than in the close-up shot.
Continuity mistake: When Roland and Cassandra are at the cafe, right before they kiss for the first time, Cassandra reaches up to tousle Roland's hair. Watch the hand she uses; it has a cigarette right before she messes up his hair that disappears.
Factual error: When the head of the icon of Jesus falls onto the handicap van the airbag wouldn't have deployed as neither the bumper sensor nor deceleration sensors would have been triggered.
Deliberate mistake: When the poolboy jumps into the pool and turns into Jesus to save Mary, the movement of his mouth does not match his lines.
Suggested correction: Mary is hallucinating, so reality isn't really a factor here.
Continuity mistake: In the scene where Mary and the Christian Jewels are performing, it's clear she only has eye shadow on one eyelid.
Continuity mistake: At the school assembly, Mary plays the keyboard. She raises one of her hands in the air, then puts it back down - but in the next shot, it's up again.
Continuity mistake: After Cassandra says that she put something rotten (ham?) into Hilary Faye's locker, Hilary Faye is seen with her turtleneck over her face. Cassandra pulls it down a bit, but in the next shot it is up again and looks unchanged.
Continuity mistake: A large group of students, led by Hilary Faye, Patrick, and Tia are snapping their fingers and dancing down the hall as they come towards Mary, Cassandra, and Roland, who are gathered near a locker. The large group comes to a complete stop and they greet the smaller group, who are shown briefly in the next shot. The following shot is of the large group; however, they are shown still walking towards Mary, Cassandra, and Roland, and they come to a stop for a second time as they continue the conversation. (00:57:30)