Our favorite family playspace has a wonderful selection of playgroups, parent classes and parent/child activities. They run in 8 week sessions, break for just some "drop in" time and start the next 8 week session.
Demand can be high for some activities, so they usually ask that you rotate out. This usually puts me in a bit of a quandary, as Daniel's favorite is just to jump into a playgroup. The playgroups are loosely structured - they usually plan some sort of craft or sensory activity (boy did he love digging in the rice and beans!), but kids are free to do whatever they like in the play area.
Alternatively there are more structured classes involving music or motion, or kids in the kitchen, or art. We tried a motion class, and Daniel was the kid "ping-ponging" around the room pretty much ignoring any directions and doing what he felt like. I'm torn about what to try next... While I think it's good for him to be exposed to classes with more structure, I would catch him looking longingly at the door to the playspace while we were in the other class. I cherish that independent spirit in my little boy who knows what he wants.