Sunflower House: fun to play in once the sunflowers grow tall! I have seen this done with on large square with side "rooms" and an entrance area. Fun for kids especially if they plant seeds and tend .making their own playhouses.
DRAMATIC PLAY AREA - Sue has gotten us a lot of wonderful, new, indoor gym equipment, but at this time of the year, I can't help but "Think Spring". Wouldn't it be fun to build something like this to put in the grass at the far side of the playground?