If you are not going to get a meal plan and are staying on campus, find out if you are allowed a refrigerator and microwave in your room. If you are, you're set because you can handle most of your sustanence needs that way.
Other ways to save cash: Parking is a big money maker for schools. If possible take mass transit provided by the school or walk if you have to pay to park on campus.
When it comes to books, try half.com as soon as you know what books you'll need for each semester, much cheaper there vs. the bookstore. Also, when selling back books, check sites like half.com, bluephoenix.com, and barnesandnoble.com. They may give you more in return for your books than the campus will.
Learn about as many of the schools facilities and services that you can. You'll find sometimes its cheaper to use their services than it is to go to a private business for things like computer repair, copies, printing, etc.
Use the schools healthcare facilities. Many times these are much cheaper than a private doctor and your school should have some time of insurance coverage for you being a fulltime student. Word of warning though, because it is cheap and convienient, its also very full so schedule things as much in advance if you can. I sprained an ankle once at school and I was told unless it was an emergency, I couldn't be seen for a week.
Best I can think of off the top of my head, if I think of more, i'll post them.