outdoor shower, corrugated metal - Could almost get away with one of these instead of trying to fit it into the inside bathroom. For a few months in "winter" it would be a bit chilly but still--fairly practical.
How to Make a Tetherball. Super inexspensive backyard toy for the whole family. harness your inner Napoleon Dynamite.) I made one of these for my kids and it was one of the most played with garden activities.