I am a Medical Assistant, how easy would it be for me to become a CNA/LVN?

I attended a (crappy) medical assisting program that I pretty much had to teach myself through. Supposedly my credits aren't transferable to a community college. I would like to become a CNA or maybe LVN, do I HAVE to take classes for these titles, or is there a way to study up by myself and take the exam...?