If you're looking for a tucked away, wildlife-rich, spotlessly-maintained state park in PA with really nice camping spots, Cowans Gap State Park is the place!
Clear Creek State Park has a scenic campground with sites right along the Clarion River - perfect for canoe, kayak, and inflatable launches - as well as trails to hike and space for your kids to ride bikes.
Little Buffalo State Park in Pennsylvania is about 30 miles northeast of Harrisburg and has a small campground and lots of options for hiking and water activities over a camping weekend.
Worlds End State Park in Pennsylvania will impress you with a variety of trails- from one with multiple waterfalls to another with a giant rock scramble!