They're sold in the pool toys section at WalMart or most anyplace that sells pool toys, usually in packs of 3 or 4--they're just balls made of cloth, about tennis-ball sized, that you put in the water and it soaks water up, like a sponge, then your kids throw them at each other--sort of like cloth water balloons. But it doesn't have to be those--you can float a couple of tennis balls, or a nerf ball, or anything else that will float and is small enough for you to cover in ant spray before they all crawl off.

Janet