You don't have to be enrolled in the college to take the pre-req or NC 1 & 2. You have to enroll however for NC3 and up. Yes, for the most part... you study, take the test, and get the credit if you pass. Some of the pre-reqs can be taken as CLEP or Dantes which, from what I understand, can save you some money. I am not much more help as I have only just started working on my first pre-req (Human growth and development CLEP...for Lifespan), but I have done alot of research over the last few years. HTH