I've been to Airworx a couple of times, as a good exercise-friendly activity with some friends. I was concerned that there would be little kids all over the place, but going in the evening seems to be past the rush of little ones. I'll tell you though, if I had a kid, I'd send them here for an hour to burn off the energy. It'll do the trick!
There are a few long "lanes" of trampolines with ramps on the ends on one side of the building, and the other side has dodgeball courts, basketball courts, and a bouncy area for small children. Though I haven't been during the day to witness it, there are some rooms and party areas that would make for a great kid's birthday party.
Jumping for an hour is no joke of a workout! With a couple good friends to talk to, the time flies by. Some of the games keep things competitive while trampolines everywhere keep us moving. It feels good to let loose and feel like a kid again!