Hi guys (and gals), long time no see...
Some unsolicited advice: if you paid for the classes, then I'd go, but otherwise the most important thing for studying for the boards is just having a plan once school is over and following it. Limit your sources as much as you can. It's better to read one book (First Aid) five times than to read 5 books. And I wouldn't start studying too early. My friends and I studied (hard) for 5 weeks. All of our question bank scores were going down by then end of the last week because we were so exhausted and sick of it.
As long as you're diligent, and have studied well for your classes, you'll be amazed how quickly the information comes back to you. I thought I had forgotten almost everything from first and early second year, but after one time through first aid it was amazing how things resurfaced.
One last thing: of all the question banks, I highly recommend USMLEworld. The questions are much harder than Kaplan, but they do a much better job preparing you. After I had gone through their database I felt the actual test wasn't that difficult (grueling yes... but otherwise ok.) If you're averaging 60% on USMLEworld, you should do well on the exam.
That's just my 2 cents, so take it with a grain of salt.