Colleges frequently provide incoming freshman with lists of things they may need for their dorms or just for classes in general. What they don't tell you--is what you don't need to be spending your money on.
BOOKS. GOT YA! You are still gonna need to buy your textbooks. However, you don't need to be buying new books. There are many other ways to get books cheap: used at the book store, check out websites such as amazon.com or half.com, and check your school's library as your professor may have a copy on reserve.
SERVICES OFFERING TO DO YOUR WORK FOR YOU. On every syllabus you receive, there will be a section on a code of conduct or ethics for class. This includes no cheating. Paying someone to write a paper for you is bad in a number of ways: it's cheating and you are not learning what you should be. If you need help, many colleges have centers that will help you, without doing your work, and it's included in the cost of your tuition.
JUNK FOOD/ALCOHOL. It's tempting, but you don't need to be spending the money or gaining the Freshman 15. It's okay from time to time, but if you have a meal plan use it! If you love coffee, make your own. College students spend a lot of money each year on alcohol. Don't drink and must if you must--go for the cheap stuff, drink were the specials are, only bring so much money with you, leave your credit cards at home.
ENTERTAINMENT. Be creative and keep it cheap. If you rent your own apartment, use your computer instead of paying for cable to watch your favorite shows. Services such as NetFlix will allow you to view as many dvds as you can a month. If you have dvds and cds you don't want--sell them. Attend events on your campus-most are free or low cost. Check out places that offer student discounts.
TRANSPORTATION. If you are living off campus, find an apartment close to campus (walking distance). Use public transportation, depending on where you go to school it may be free with a college ID.
WORK OUT. Use your school's facilities, run around campus, enroll in on campus exercise classes--instead of joining a gym.