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.
we have been trying to come up with an idea around the trees towards the end of our yard. "If you have a leveled yard and trees, try this awesome DIY project. People of all ages will enjoy this mini sun deck.