First things first - print out the free template printable on a single sheet of white cardstock paper. Print one sheet for each person/craft you want to make.
Next have children press their thumb on their desired colors of ink pad and then press it down on the "branches of the tree" in the printable.
Repeat until you have all the "lights" on the Christmas tree you want.
Finish off your Thumbprint Christmas Tree craft by adding other embellishments you see fit {like glitter and sequins with glue!}