I think they're a little young for Edaville. Try Southwick's Zoo in Mendon or the Roger Williams Park Zoo in Providence. The Zoo is part of a big park where there is plenty of shade and places to picnic. The Zoo has exhibits appropriate for young ones as well as things for other kids. Take a stroller and a picnic. There is a snack bar but you can bring in your own food. The Ecotariam in Worcester has some tot-friendly exhibits and an outdoor zoo (small) as well as a tot play area indoors and a small playground outside. There is a train ride around the grounds which is fun - there is a tunnel and the engineer invites everyone to yell as loud as they can while passing through - avoid that if your kids don't like noise. But you can watch the train go by while roaming the outdoor animal exhibits and the passengers always wave to people they pass. There is a Children's Discover Museum in Acton with 2 buildings - one is for older kids but the main one is a converted house, with each room dedicated to a different theme (water/bubbles, jungle, nautical, diner, etc.) - Definitely fun for all ages. Bring a change of clothes in case they get a little wet in the water room - there's a water table but the kids can get a little drippy! Boston Children's Museum is also great. Sometimes the public libraries have passes so you can get in free or for a reduced price - reserve ahead if you can. If you find a place you like, take out a membership - then if you go and the kids poop out after an hour, you don't feel like you've wasted your money, and you can go again and again. Have fun!