Breakers water park is a great place for a Hot Arizona day. Entry fee is decent, you can find coupons at circle k's accross Tucson. It's not the best water park, but it will do. There is a snack bar, bathrooms were dirty. All in all the kids had a blast!
Breakers is Tucson's only water amusement park. They have Arizona's largest wave pool as well as a number of different types of water slides and a water area for smaller kids. They're open from May through September every year, so just in time for the weather to get really hot in Tucson! This place is fun for kids, but also for adults. I started going back in college and always had a great time. It does get crowded, but that's to be expected anywhere that offers relief from the heat in Tucson.