Not too easy. Not too difficult.
For about a week after I moved in, the weather was awful - 90+ and really humid. With no air conditioning in the dorms, it was pretty awful being in your room.
However, there are some spots that are air conditioned, and if you can find them definitely hang out there when it's humid! There has been some weird weather recently where it has been pretty cold, but if you have a sweater you'll be fine.
Hours per week:
Advice for students:
Winter is coming up and it snows in Boston, so bring warm clothes, but I've heard that they clean up the roads and sidewalks really well. Just don't take summer classes - you'd die from the humidity!