Two suggestions.
Hersey Park in Hersey PA. Nice amusment park, some cool rides. Also you can tour the chocolate factory. Good times.
My other suggestion is about 5 1/2 to 6 hours away. Washington DC. There is a TON to do there, and it is all free. Museums, momuments, etc are all free, no price for admission. All you have to pay is gas, lodging and food.