I'm a broke college student, working a minimum job wage capped at 25 hours, without support from my parents. What other things can I do on the side to help as a "secondary" source of income?

Getting a second job has crossed my mind many times, but I simply don't think I could handle the stress, and leaving my current job isn't smart because I work for my university, and it has a lot of downtime so I am able to work on homework at least some of the time. School policy is only 25 hours per week while the school is in session, and I have no external help from my parents, so I'm living paycheck to paycheck while racking up more and more debt. I graduate in a few months, so I can keep going by for the time being, but a little extra cash on the side would do wonders for my sanity.

I also wish it was a matter of cutting back. I'm not a big drinker or partier, so thats not something I can cut out. I don't go to sports games, concerts or other events that can be cut out, I do my best to shop frugally whenever possible, and I limit my entertainment to the bare minimum. I only eat out when my girlfriend is in the mood for it which is only once or twice a month.

Any suggestions? I've looked into donating blood, but there is not much that I can find in the area. My girlfriend even suggested sperm donation but I don't know how feasible that is, let alone the awkwardness of the entire thing.
Thanks guys.

Edit: Since people are asking more specifics about my finances, I earn roughly 800 per month and my rent is 500 plus utilities. So its obviously not at all a good balance, but it's the cheapest I can find in a somewhat good area, but I have had to go into debt for food, that's for sure.

Edit 2: I don't wish to quit my current job, it is minimum wage ($10 an hour where I am), but its for my school in the department that I could potentially work for after I graduate (plus I like to think I'm well liked by my departments leadership, but I could be wrong about that), and it also is extremely flexible with my class schedule, so I don't have to worry about getting on management's shit list for my slightly unfavorable school schedule this final quarter. I also only have to bear through it for a few months, so I'm not looking for a long term solution, just something to keep me above water for the next 10-12 weeks until I'm graduated and (hopefully) find gainful employment. I worked for Geek Squad over a year back and have considered returning, but the combination of inflexibility with my currently locked in school schedule as well as the stress I will have from an overload of work and school work, I don't think it would be worth it in the long run.

Edit 3: I have no car or a bike