what does an elf on a shelf do

An elf on a shelf is a toy that is designed to keep a watchful eye on children and report back to Santa Claus about their behavior during the holiday season. The elf usually sits on a shelf or a window ledge, watching the child and making note of their actions. The elf will then fly back to the North Pole and report to Santa about whether the child has been good or bad. Some elves are even programmed to move and make noises to scare the child if they are misbehaving.