Lots of great suggestions above, but I'll add one more. If you're going to be near the waterfront, across the street on the Rose Kennedy Greenway, there is a really fun fountain that the kids play in. My DD could spend an hour there with no problem, and I think she thought it was the best part of her day.
However, I can't really recommend the aquarium. I think it's smelly, too crowded, and way overpriced. Plus, it takes our family less than an hour to go through the whole thing (and we're the type to read all of the information at each exhibit, not just breeze through).
If you go over the Constitution, you can take the MBTA water shuttle. It's a really cheap way to take a little harbor cruise.
And I'll second the suggestion to visit The Butterfly Place. We went there last fall and DD had a blast. I was really surprised at how good it is there. And there's a picnic area in the back if you're interested. Like the PP suggested, we went to Kimball's afterward for ice cream. There are also pony rides and a petting zoo there (as well as mini golf, go carts, batting cages, etc.).
This is south of Boston, and it sounds like you'll spend more time in the north, but Plimoth Plantation was a lot of fun. In addition to the Pilgrim stuff, there's a Wampanoag Native American Village run by authentic, modern tribe members, which was really informative. We also visited the Mayflower II and learned a lot.
However, I can't really recommend the aquarium. I think it's smelly, too crowded, and way overpriced. Plus, it takes our family less than an hour to go through the whole thing (and we're the type to read all of the information at each exhibit, not just breeze through).
If you go over the Constitution, you can take the MBTA water shuttle. It's a really cheap way to take a little harbor cruise.
And I'll second the suggestion to visit The Butterfly Place. We went there last fall and DD had a blast. I was really surprised at how good it is there. And there's a picnic area in the back if you're interested. Like the PP suggested, we went to Kimball's afterward for ice cream. There are also pony rides and a petting zoo there (as well as mini golf, go carts, batting cages, etc.).
This is south of Boston, and it sounds like you'll spend more time in the north, but Plimoth Plantation was a lot of fun. In addition to the Pilgrim stuff, there's a Wampanoag Native American Village run by authentic, modern tribe members, which was really informative. We also visited the Mayflower II and learned a lot.