Water Race
Position two players on opposite sides of an oscillating sprinkler. Each player has a cup. As the sprinkler falls from one side to the other, the players try to fill the cups with water. It sounds simple, but there is a catch. You can't move your feet. If you move to attempt to retrieve more water, you have to dump the cup of water on your head. The first player to fill the cup with water wins the game.
Sprinkler Jump Rope
Let the children turn a long jump rope in the middle of the sprinkler water. Allow the kids to take turns jumping in the water. They can jump for fun or you can make the game competitive. To add the competitive element, let each child hold a cup as he jumps. The child who collects the most water in his cup after a certain time frame is the winner.
Musical Sprinkler
Position someone at the faucet to turn the sprinkler on and off. Turn on the music and let the children dance, jump or pose in funny positions in a circle around the sprinkler. When you turn the sprinkler on, every child must freeze and get soaked by the water.
Sprinkler Limbo
Turn the sprinkler on and let the children walk in a circle around the sprinkler. As they circle around the sprinkler, they get lower and lower. They can bend over forward or backward. They can crawl or walk using their hands and feet. The child that can get to the lowest point and continue to move around the sprinkler wins.