After the water fight is over, or every hour or so, have a race to see who can pick up the most broken water balloons until they are all picked up. Use a plastic milk carton to collect them in, the spout is small enough to collect them and little hands can't reach in and take them out. Remember, these little broken balloons are a choking hazard, not only to small children, but to anyone. If a balloon breaks in front of a child's mouth they can suck in the balloon when they gasp with surprise,and it can choke them. You will need one raw egg and one spoon for each person participating in the race.
Line contestants up next to each other on a starting line.
Place the egg in the spoon. The racer must balance the egg in the spoon, without using their free hand, and make it from point A to point B and back to point A again. This race works best with Rubbermaid containers, the size that you can fit snugly into your kitchen sink. Mark the inside of the container with a marker and fill with water to that marked spot. Howeverm in this race, each contestant runs solo.