Elf house on a tree! That would be cute in the garden, especially in the tree over grown with ivy. How about some battery tea lights in the windows during outdoor parties. I hear the fairies/elves whispering "home school project" in my ear.
Bowls made of confetti! Great recycling art project--save all those leftover paper scraps (put in small bowls at each table). Collect a bunch and have the kids cut them up; Then make bowls made from confetti.