Amazing Indoor Gym Birthday Parties: Kids U
If you're looking for a great indoor gym birthday party, take a look at Kids U in Needham. We've been to a bunch of birthday parties there and they are great fun for the kids. They tend to be about 1.5 hours and the kids play in the PlayQuad for 30 minutes, then go into the Gym and play games with an instructor for 30 minutes, then have cake in the kitchen for 30 minutes. The Gym has a cool long trampoline that the kids love. The facility is brand new and fabulous with its amazing PlayQuad and Gym. Kids adore the playquad and could play in it all day. I'd say it's best for ages 4-7.
Now called KidsStreet (www.kids-street.com) and no longer affiliated with the KidsU.com chain (not listed on their site). I haven't been there, but wanted to save confusion for others.