Really check more into Knoebels. They have many buy on get one days- and what we have found is we buy bands for the kids- and we pay as we go. (Generally are doing only coasters and train oh and the carousel.
For us it's really the cheapest park - no parking fee, the food is inexpensive and delicious.
So while it might be out for this weekend- keep it in mind for the future.
I'm going to watch this thread for ideas! We are going to start Geocaching- basically hiking with a little prize treat added in for interest for the kids. and it's FREE once you get the GPS.
http://www.geocaching.com/
great site with local places.
My kids really enjoy that little zoo- the Lehigh Valley Zoo- but what they really enjoy is the drive around the back of the zoo- over to the stream. The picnic we have and then the drive around to see the bison! And that is all free. You could skip the zoo and just do Picnic- and see the Bison.