Stay wet all day long...and never get cold. At forty years old I felt like a kid again. I loved the family atmosphere and the lazy river rides. The views of the Comal River meander by as you ride on your own man-made rivers.
With two full parks this is a full-day adventure (both included in one admission price). The larger main park where most of the rides reside and definitely where the rides are more geared toward families. Later, when you're ready to try the Master Blaster and other rides that take more courage, take the free shuttle bus over to the second park and go crazy. My favorite is the Torrent which is really just a big man-made moat that flows around the tube rides. I'm not sure why I like it, maybe it reminds me of the ocean with swelling waters that build and recede.
Tips: Wear strap-on sandals or water shoes. The concrete can get really toasty and you'll be begging for something to protect your soles before long. I made the mistake of wearing flip-flops and kept having them fly off during the faster rides. I got pretty good at gripping them with my toes, but water sandals with straps would have been ideal. My husband and son, who being big menly-men, didn't need no stinkin' sandals. The concrete and sun chewed the bottoms of their feet raw and they admitted they had made a mistake going shoe-less.
You can bring your own food (picnic) into the park. Most people find a picnic table and stake their claim for the day. They also have lockers, but you may have to rent two or three of them to hold your things. They are open end of April through mid-Sept.