Continuity mistake: After Sarah has called at Harry's office, Harry prepares to open his office door to see her out. The camera cuts back to Sarah for a moment, then back to the camera angle on Harry as she walks to the door. In that short space of time, the sliding cupboard doors have changed their configuration, and the blinds in the upper left of the frame have partially closed. (00:18:45)
Visible crew/equipment: In the scene where Buddy and Michael are leaving the school, a crew member is visible in the bottom left of the shot. At first, he is just standing there, but he then tries to hide inside a doorway. (00:52:00)
Continuity mistake: In the scene when John Ritter is trying to fire Santa and the elf, there is a cup with candy canes on the edge of his desk. The number of candy canes change with each shot. (00:32:20 - 00:34:10)