Splashpad -- a fun, safe, inexpensive (compared to a pool) water play option for your yard. The play area looks like stone, but it's actually a springy, spongy, recycled rubber material. No skinned knees on this surface.
Emily Henderson - outdoor kids area that's not an eye sore!
used an old rain gutter, with end caps on each side, and a small pump, to create a flowing waterway for plastic boats. kids loved it