123 on the Museum of science, The Aquarium, The Duck tour and Salem. If you go to Salem, look for Susannah Martin's headstone.She's my Great Great Great Great Great Great Great Great Grandmother
Also, something nobody has mentioned - Quincy Market. There's lots of yummy delicious food, cute little shops and such. Last time I was there, they had a bunch of street performers that were awesome. One guy was throwing and spinning fire!