Continuity mistake: Annie's body changes position on her front steps. At first her head is on the edge of the sidewalk and Mitch doesn't move her. Then after he runs to get Cathy he comes back and covers her with his jacket and her head moved about six inches from the edge of the gravel sidewalk. (01:30:20 - 01:31:35)????
Continuity mistake: As Mitch checks the doors and windows he returns to the living room and everything on the table has been rearranged and no one moved from where they were sitting. He's not there but his cup moves from the being next to the edge of the tray to being adjacent to the handle. (01:38:15)????
Deliberate mistake: Some of the children that are running in front of the superimposed background were never in the classroom. For example the blonde girl in the blue and white sweater in the middle of the second shot and the girl in the green sweater in the center of the third shot were not there. (01:13:40)????