N.W.
The Warren swim lessons fill up quickly. We took swim lessons at Lifetime. They have a zero entry pool and you do not have to be a member to take lessons. We really enjoyed them.
I also did a gymboree music class with my son when he was 9 mos old and he loved it. I believe you can also get a summer pass to gymboree.
I would look into Sterling Heights programs as well. They have a lot of great stuff for kids... most of it during the day.
Rochester- RARA also has some wonderful programs and it's must a short drive for you.