I camp at Grass Point State Park every year for two weeks. There are several non-electric sites near the water that have plenty of room and you can watch the ships go by right outside your door! We also take our boat with us--you can rent a small boat right at the campground if you're feeling adventurous.
Grass Point has a nice beach and playground for the little ones, also a brand new bath house. Don't forget the village of Clayton while you're there--nice restaurants and a great antique boat museum.
2009 Jayco 17C, 2015 F150, 2004 Ford Ranger