This isn't that far for you but if you have never been there, you have to go to The Farm at Walnut Creek. It is an Amish "zoo" basically where you take a horse pulled wagon ride through their grounds. An amish man drives and is the tour guide. You are given a bucket of food and you feed the various exotic animals that come to the wagon; the giraffes at the end are the finale. We went with our young teens and we all laughed so hard, there was something so exhilerating and funny about being this close to these animals! There is also an area to walk through with other small animals, a fun gift shop and it is all beautifully landscaped. It would be lovely in autumn I'm sure.
I imagine you've already been to places like Kalahari or Great Wolf Lodge. That's a great escape with kids.
Pittsburgh also has wonderful museums, ...and the Columbus Zoo is one of the best. We went specifically to see the new exhibit with the swimming polar bears.