On-The-Go Mini Playsets (Camping Hacks)
LEGO Duplo Mini Golf - adorable idea for your
Fun with water, great recycled plastic bottle project. This could be pretty if you used wine bottles. It's just a matter of figuring out how to cut a hole in the side.
DIY Kids Water Wall by playingbythebook via curbly. this is more about play, but I think something a little more durable with this same idea might go well in the sideyard garden/play area.