Other mistake: When Jack first arrives in Christmas Land he doesn't know what is falling from the sky (snow) but he somehow knows that the children are throwing snowballs.
Continuity mistake: One of the tiles comes loose when Wallace is walking across the ceiling in the museum. A few seconds later, the tile is flat against the wall again.
Continuity mistake: During Batman and Joker's fight, Batman kicks out one of Joker's teeth. Later on when Joker puts on his jet pack and starts to take off, he has all of his teeth. But in the next shot his tooth is missing again.
Continuity mistake: When Bob tells Junior that Larry is a cucumber, the carpet and the shadow of Junior's bed shift to the right a little bit.