Thanks for the tips everyone. I knew the 2 options (pay lowest amount first, or pay highest interest first), but didn't know if there would be a difference for student loans (federal vs. private). I guess there technically is, since the federal loans have the fixed interest rate.
I'm going to pay off the highest interest rate variable loans first, and once those are paid off I'll try to finish up the federal loans. I'm making great money right now, and have been working across the country (ie my company is paying my rent, car, gas, insurance, plus a nice per-diem) so I literally make money on my expenses. Also, the loans are through 2 different lenders, so I'm only paying twice a month (not 6 times a month).
I'm not in a HUGE hurry to pay them off, but I'm planning on spending about $15,000 on an engagement ring in the next 6-9 months, which I already have the money for. I could just take the $25000 and finish up all my loans, but then I'd be financing the purchase of the ring come next summer! I'm also planning on purchasing a condo in Chicago in 3-4 years, but I'll be working with 2 incomes at that point