Oh, that's a fun one! The elf on the shelf tradition has been around for quite some time. It's when a special elf is sent to observe a child's behavior during the holidays. If they've been good, the elf rewards them with a treat or a gift. If they've been bad, the elf reports back to Santa Claus and the child might not receive a gift. It's a way to encourage good behavior and make the holidays a little more exciting!