We love this place. The price is $5 for adults, and I think $4 for kids, but we buy a family pass for $140 that pays for itself after just 7 visits (we drive the 60 miles to this place at least 3 times per week).
It's best to be 48 inches or taller to enjoy all things. If you can swim (by yourself without life jacket or floaties) the diving boards are a blast for any size. My daughter has been going since she was just 2 (and an excellent swimmer). The "family slide" is the extra wide slide and parents can take their children under 48 inches. The lazy river is a huge hit for kids under 48 inches because it connects to the other (48 inch required to ride) slides. Makes it nice for my 47 and 3/4 inch kid to enjoy other things while her brother enjoys the over 48 inch!!!