One of the children in Charlie's class during Parents Day is an elf with pointed ears, which can be clearly seen when Charlie pulls the snow globe out of his backpack. When Charlie tells the class that his dad is Santa Claus, the elf boy is the only one who doesn't laugh.
For one week in November 1994, Tim Allen had the #1 movie at the box office, the #1 rated television show (Home Improvement (1991)), and the #1 New York Times best-selling book ("Don't Stand Too Close to a Naked Man").
The dance that Tim Allen, Eric Lloyd, David Krumholtz, Paige Tamada, and the other elves do, to ZZ Top's "Gimme All Your Lovin" during the montage before Scott's second Christmas Eve as Santa was improvised and done in one take. The director kept it because it was so good.
There are several portraits of (presumably) past Santas on the wall of Santa's bedroom. This shows that this is not the first time that the reins have changed hands, confirming the film's main plot point.