how does elf on a shelf work

Elf on a Shelf is a Christmas tradition that involves an elf doll who is said to be watching over the children in the household. Each day, the elf is moved to a new location, and the children have to find him. The elf is supposed to report back to Santa Claus about the children's behavior, so they need to be on their best behavior to get on the Nice List. Some families even have an elf that brings little gifts and surprises for the children.