The park at Swains Lake is really nice.  There is lake access to fish, playgrounds for the kids, and a nice pavilion.  The campground sites are pretty close together.  It's a nice place to camp during the week, but it did get really crowded on summer weekends.  I will say the shower house is GREAT!  Individual showers with locking doors for complete privacy.

The location is great to day trip around the area.  We enjoyed a day in Kalamazoo.  Jackson isn't far with major grocery stores and shopping.