My best advice would be...
- Bring an empty vile, go early to the game for batting practice...Stand by the home-plate area and ask someone who has field-access to please fill your vile up with dirt from the field. (I did this, and it is extremely awesome to have dirt from home plate at Fenway Park). You can ask your tour-guide, but mine said no - FYI anyone who works at Fenway will most likely say no, so ask someone who looks like a fan who has field access for batting practice.
- Go visit the library...Amazing building filled with awesome history, just to say you were there is worth it. Also, Good Will Hunting filmed a scene there...A+
- Boston Harbor is beautiful/gorgeous/solid - worth taking 30 mins to walk around there
- Go to the Fenway Park tour / Visit the official Boston Red Sox store on Yawkee Way
- Go to the Cheers bars - not impressive, but it's nice to say you've been there - not a drag by any means.
- Downtown has some nice shops including a pretty good size 4ish floor Nike Store
- Have fun - Take it all in - Be proud you rep the best team in organized sports, and that you are part of the best fan-family-mob ever...slap hands with some fans at the game.
- Order one of those Lemon/Ice drinks when you're at your seat during the game when the drink-man comes by - If you order peanuts, they throw them at you and then come collect the money, so don't duck and let them hit the lady behind you, catch that s***!
Word - all I can think of for now
Hope you have the time of your life - Guarantee you will go back annually