I'll have to research the sport camps...that would be nice if we had something like that but I've never heard of it in our area...
Here the sports camps are all run by the Parks and Rec department, so check through them, too.
Summers are hard for us. One of my kids needs to be on the go or we have behavior issues (and he doesn't like staying home doing crafts and projects) and another who battles fatigue and can't handle days full of constant activity. So the one who needs to be busy will do 6 weeks of camp through the parks department. 2 weeks will be baseball camp, and 4 will be a more general camp. The other 2 kids will do a morning camp or school program for a few weeks but mostly be with me.
For the 2 who will be home with me most of the summer (and my 3rd during his non-camp weeks) we'll go swimming, to the library, many different playgrounds, the sprayground (water play area with sprinklers), do crafts and cooking projects, playdough, and lots of other low key stuff. I'll check out the bowling link here, and a few movie theaters in our area offer low cost matinees for kids once a week. I always buy some new craft supplies, water guns, etc. at the start of summer and we'll get a lot of mileage out of those, too. I haven't been good at arranging summer playdates in the past, but I'm hoping to plan more of them this summer.
At some point later in the summer, when the kids are getting bored, I'll take them to the toy store and let each of them pick out a few new activities or outside toys. That usually helps get us through a few of the later weeks when they're tired of everything we've been doing.