I was going to suggest Woodward West since I know that had a Tramp and Tumble section of their gymnastics program in the past. But it's been 10 or 12 years since I've been there. Checked out their website and looks like West doesn't have a program anymore(they have switched to an acro-tumbling program like the new college sport that focuses on tumbling and stunting) but Woodward East does have a program they call "Power Tumbling". Brochure says it "focuses on rod floor tumbling, double mini and trampoline to teach both compulsory and elite level routines but not competitive trampoline". I'm not sure what they mean by that, maybe it has to do with the type of trampolines they have? Might be worth a call to them to see what they mean.