Working more than 20-hours per week will start to have an effect on your grades, but whether you are looking for more money, more experience, or both, working for 10-15 hours/week can help you out a lot when you are in University.
Studies show that half of the students who work while in college do it either in retail/sales or in food service. However, I think that a student’s best bet is in the following areas:
1) Receptionist. Although the pay isn’t great, you are often being paid to just sit there. During your slow time, most employers don’t mind if you do homework as long as you are alert.
2) With a Professor in your area of study. Through your univerisity and in separate ventures, many professors are looking for students to do the boring parts of their work, or to help out on studies. When I was in undergraduate, I used to help with an economic professor’s behavioral studies, and he paid me well above minimum wage. But, even when this option doesn’t pay a lot, it can be great. It is [particularly good for your resume and/or if you want to continue in academia.
3) Paid Internship. More and more internships these days are paid. Even 10 years ago, when I started out as a Theatre major, I was able to find a paid internship. The big plus was that I got school credit for the internship, a weekly stipend, and an room in an apartment. Later, I was able to get an internship in PR for a few bucks above minimum wage. Both of these internships got me money, experience and school credit. That is a hard combination to beat.
4) Nighttime Baby-Sitter. Before wrinkling your nose at the mention of babysitting, remember that many parents like to put their kids to sleep themselves before going out. They are willing to pay a premium for a responsible, mature college student, as opposed to a teenage brat who might do who knows what with her boyfriend while the kids are asleep. Many parents are even happy if you sleep on the sofa if they are out. Whether you sleep, or do homework, you are basically getting paid to do what you should be doing anyway.