Cooch is exactly right. Vermont Transit runs buses from Boston to
Manchester and there schedule is available online at
www.vermonttransit.com. They also tend to run mostly on time and
have student rates, although I don't honestly know the cost from
Manchester to Boston. I can tell you that Hanover to Manchester,
which is a longer trip, was $20.
As for things to do in Manchester, there's not much. The airport's
nice!
Michael Philpy