Aerials Gym at 6001 Coit Avenue Northeast, Grand Rapids, Michigan.

My friends and I have gone to A&B during open gym hours quite a few times and have always had an awesome experience. The instructors are very knowledgable and great at teaching you how to do tricks the right way without hurting yourself; they were also very hands-off unless you asked for help which was nice.

They have a full range of gymnastics equipment, a climbing wall, and over a dozen hand-woven trampolines that give you an incredible workout. It makes you feel like a little kid again, except that these trampolines are nothing like the ones we had in our backyards growing up; they have way more bounce and give you a much softer landing which is better on your spinal system.

I highly recommend it for any age group and it was only maybe $7-8 for a 2 hour session? One thing to keep in mind is that it gets fairly crowded when school is out.