I agree with the above comments- every penny you spend will be money you'll pay back plus
interest. If you steer clear of using your refunds, that would be best. I have loans that end up being a big chunk of a refund every semester, but all of my refunds end up in my savings account for emergencies
. My husband and I both work, and a hefty amount of my tuition is paid for by scholarships, grants, and tuition assistance from the hospital I work at. My loans end up being an emergency fund- for instance, when my work claimed they didn't receive my tuition forms last semester? I dug into my refund account.
The above comment sums "necessary" up well, "Necessary expenses are those keep you from starving, freezing to death, or failing your classes."