Well it would depend on what area, but the whole state is loaded with parks. There is dorneypark in allentown, hersheypark in hershey, knoebels in elysburg, waldameer in erie and kennywood near pittsburgh. Then there are some smaller parks that are worth while going to like delgrosso's and lakemont which are both near altoona , and there is ildewild below kennywood, and dutch wonderland in lancaster . I guess that is about it. Here is a link to rcdb.
www.rcdb.com/qs1.htm?quicksearch=pennsylvania
Thanks so much! He just left Texas yesterday for Corning, NY - just over the PA boarder. We are starting to plan our first trip to visit!