After the demise of our last kiddie pool I decided I'd try another route. With a tape measure in hand, I scoped out the big old playground in our yard, hit the Home Depot, and two days later we had a water park, complete with a water slide!
Here's a quick video tour:
Step 1: Planning and Parts
Since I was building mine around a playground that was already in place, I simply took a pen and paper and a tape measure outside and started measuring, marking, and noting down what sort of fixtures I'd need. If I was planning a new playground, I'd have included this into the original design.
The final design required about 45 feet of 1/2" PVC, a number of 90 and 45 degree angles as well as three way splits and end caps. Home Depot or Lowes or whoever should have a pretty big selection of these. I didn't know it, but garden hoses have a different thread than standard 3/4" pipe thread, but they've got an adapter for that too.
I found the sprinkler heads further down the same aisle. I guess they're designed for those below ground watering systems, but they worked just fine for me!
The final thing you'll need is PVC cement and primer. I bought the smallest cans of them that I could, and there's enough in there to last me until the sun explodes.