A great way to spend a good part of the day is to have they kids set up their own carnival. One day this summer I did this with the kids I was watching and their neighbors. I told them to come up with one carnival game. They each set up their own little stand and found prizes to give out for their game.
Once everyone was ready, we went around to the different stands. Each was able to play every game and to lead a game.
The kids loved being able to be in charge of their own stand and had a blast playing the games. Let me know if you have any ideas for more carnival games that we can use in the future!