Great Brook Farm State Park is a great place to spend your weekend with the kids.  They have a lot of nice hiking trails (in the woods) and a working farm with cows, goats, pigs, chickens and sheep.  They even have ice cream too!  My kids just love it.  All it costs is $2 to park.  With these beautiful weekends we have been having, it's a great way to spend a Saturday afternoon or a Sunday morning!