When my mom was here last week, she introduced the kids to swimming in rubbermaid containers and inflatable infant bath tubs. And they loved it! But we didn't have anything big enough for the two of them, and I wanted something that had a cover so that when they were done swimming (but not done playing outside), I could cover it and not worry about them falling in when I wasn't looking. So we bought this big plastic crab that is supposed to be a sandbox, but it works just as well with water. And I figured we could also get some of those plastic balls and use it as it ballpit in the cooler months.