In my case, I was trained as a CNA in Illinois and worked in a nursing home shortly before moving to Minnesota and transferring to the University of MN. I began working for a group home company that did not require CNA certification even though the job description was that of a CNA (the company developed their own training program). After working there for 2 years, I realized I had let my Illinois CNA certificate expire because I had not worked a shift in IL during that time. This was frustrating because I had just received news that I got accepted into my nursing school which required an active CNA cert as a prerequisite , even though I've been working as a "nursing assistant" at the group home for the past 2 years. I was extremely relieved to find out that Minnesota offers you the chance to challenge the CNA state competency exams without having to retake any training.
My friend borrowed me her CNA text book (Mosby's textbook for NA 7th ed) and I just studied from it and watched videos from CNA Skills Videos | Kamanga CNA Training, Inc. CNA Training in Washington State
to make sure I was following everything by the book. Thankfully, I passed the written test (60 questions?) and skills test (5 random skills out of 21) and officially became certified as a CNA in MN.
So if you're looking to get a CNA cert for cheap, MN lets you challenge it. However, if you haven't had any clinical experience, I would strongly suggested that you take the class so you can practice your direct patient care on actual people.