How about using them as bases for those wire Christmas card holders you always see? You could either twist the wire stems and holders in advance or use pipe cleaners. Then you would reinforce the cupcake holders with cardboard on the bottom and stick the wire through that, so it stood up like a tree. You have a loop of wire at the top to stick Christmas cards in. Kinda complicated for little kids but you could do part in advance maybe, and everybody needs to put their cards somewhere.
Mmm, I love cupcakes, you could just have a huge bake-a-thon of cupcakes.