The Trustees of Reservations manages 120 special places around Massachusetts, protecting sites of ecological, scenic, and historical importance. This membership entitles 2 adults plus children under 18 to free admission for one year at any of the Trustees locations, including the DeCordova Museum, Appleton Farms, the Crane Estate, and the Fruitland Museum. It also includes 50% off for admission to Crane Beach.
BONUS: You can join the National Reciprocal Museum Association through this membership for a cost of $70/family. This entitles you to free admission at hundreds of museums around the country, including Discovery Museum in Acton.