It is certainly possible to work part-time while attending school full-time. I am finishing my final semester of nursing school and during all 4 years I worked an average of 20-30 hours each week. While this may be extreme (and certainly not recommended by faculty) it was very possible and I still maintained above average grades. In fact, my time management skills have improved vastly and I gained great experience in the healthcare field; so working actually benefitted me by more than just a paycheck.
I would suggest looking into local healthcare facilities that may need part-time help. Most places love to hire nursing students because they appreciate their hard work efforts, view you as a potential RN, and therefore are willing to offer some flexibility. I worked for a home health agency for the past year and I tell them what days and hours I'd like to work.