Ideas on a trip to New England with toddlers

We are looking to take a short trip to New England in September with our 2 and 4 year old. We’ll probably fly into Boston and stay there for 1-2 nights then go on to our next destination, preferably no more than 3 hours from Boston.

I went to down east Maine last year with friends and loved it. However, I think with two littles we should maybe do something a little different but I’m torn on where.

I’d also love recommendations on what to do and where to stay in Boston as well.