I used the hand print Chrismtas tree idea with a class and the kids LOVED it! I had premade a bunch of hands to make the tree as big as possible, as well as a tree topper (so they wouldn't fight about who got to make it). I also prepared a bunch of colouring sheets of ornaments for the tree, so each kids got a hand print, an ornament, a candle and present under the tree (all cut out before the class). I used several kinds of green paper found at local craft stores and a piece of brown felt for the stump. If I had had more time, I would have used more hands to make the tree bigger.
I'm attaching my file with all the colouring images. It was a lot of cutting a glueing but it was sooooo worth it!
(I didn't let any of the kids use the scissors or glue in my class, knowing what a disaster that would turn into...)
Thinking back, to improve the tree I would have premade a tree shape cut-out from green paper to fill in with the hands.
It's hard to tell from the images posted but the end result is actually about a meter tall!