PVC Sprinkler Water Toy - how smart is this? $10 worth of materials from the hardware store will bring lots of joy this summer. :) My friend did this with her kids and used a couple of pipes and plastic streamers as well, they called it a "car wash" and rode their bikes through it. They played with it all summer.
fishing in a kiddie pool
Make your own water table using a small pool and overturned crates- frugal!