how does the elf on the shelf arrive

The Elf on the Shelf is a special little elf that is brought to each family to help Santa keep track of who's been naughty or nice. Each Elf on the Shelf comes in a special box with a note from Santa, explaining that the elf is there to help keep a watchful eye on the kids. Once the box is opened, the elf will come alive and can't be touched again. The elf will then watch and report back to Santa on how the children are behaving.