Boston living is pretty expensive. All of this is for full school year not including summer. Co-op really wont change your living expenses besides travel. If you really pinch you can reasonably hit the low numbers, if you want to live well but not splurge the high numbers will be your cost (nicer housing, better food).
Given in (minimum possible - maximum reasonable format)
Freshman Year In School:
8k housing (dorms) +
6-7k food (meal plan and food out / snacks) +
0-1k other expenses
= $14,000 - $16,000
Sophomore Year+ and Off Campus Living (in school or on co-op):
9k - 11k housing
3k - 5k food (no meal plan required anymore)
0-1k for travel
0-1k for other expenses
= $12,000 - $18,000
Do note that about 14k is assumed in the school sticker price of around 60k. So if you go the high end, the cost per year will be 64k. If you go the low route, it will be 60k year one and you can probably shave off 1-2k by not doing the meal plan which may end up coming back on for travel / other expenses.