a current student here
Being a major metropolitan area, things are going to be a bit more expensive. However, with some patience and a proper use of online resources, you can find a lot of things to do for pretty cheap. BU also provides a lot of resources for these kinds of deals. For example, on the weekends, you can get movie tickets for half the price and if you attend some symposiums and various school-sponsored events, you can get free food and free tickets to different events. For example, I went to this art exhibit for students and I get a free ticket to the Boston Symphony.