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.
I love these things because my Father used to make dollshouses & furniture & fittings for them out of bits of everyday things - I recall him painstakingly cutting brick shapes from the sides of matchboxes for the external brickwork. So much patience!