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.
A branch screen. remember idea: branch screens, built in planter boxes on rolling casters. Creates a moveable screen, with independent ivy growth-bonus boints for creating hinged, double screen frames that will collapse for moving or customizable sizes