It's a big city, but you can cover the center on foot in just a couple of hours. And with the history of the Freedom Trail, the modern attractions of the Institute of Contemporary Art and everything in between, Greater Boston is worth exploring for a weekend, and for years to come.
Hop on the T for a quick ride to the Kennedy Library and Museum, or stay close to the water for a visit to the New England Aquarium. When you're ready for a coffee or ice cream break, a short walk to the North End will put you in the midst of world-class dolci on Hanover Street. Take the kids to the Children's Museum, where they'll have so much fun they won't even realize how much they're learning.
Just across the Charles River in Cambridge, enjoy the ethnic cuisine and plentiful bookstores of Harvard Square. If you're scientifically minded, the MIT Museum will give you a lot to think about. Also in Cambridge is the Museum of Science, where you'll catch fascinating exhibits and a Duck Tour amphibious vehicle.