I have a sprinkler, mini pool and I use disposable turkey pans with water for the little ones. My daughter is 10 months and I have a 12 month and a 14 month. My son is 3 and a half and I am also caring for a 4 and a half two days a week for the summer. When I have the three little ones outside it is only the sprinkler and turkey pans that are out (although pool is little, three little ones is too risky to me). During afternoon nap for the little ones, I fill up the pool and let the bigger ones get in to cool off. If I only have the big ones for the day, I will take them to the wading pool. Two lifeguards on and parents have given permission. My rule with the mini pool is...if they are old enough to get in and out on their own without falling every time, then I can have it out. It will be next summer before I can have it out all the time.