when does elf on a shelf appear

Elf on a shelf appears on the night of December 1st, when the elves start preparing for the big day. They visit all the good children and bring them gifts. They also bring toys to the children who have been bad, but these are not the same toys that they would give to the good children. Instead, the elves give the bad children coal or other unpleasant items as a reminder that they have been naughty.