CLASS is short for Christian Liberty Academy School System. I am currently using this with my daughter. I found out about it from another work at home mom. Basically what you do is enroll with the form on their website. Once you send it in you will receive a CAT test for your child to take. The results of that will determine what curriculum CLASS will send your child.
You have 12 months to complete each school year, but you can do it in less if your child is ahead. What I like is that once you finish one grade you can move right in to the next one if you want.
The absolute best thing is that CLASS will do all the grading and record keeping for you. You will be provided with report cards and transcripts. The cost is only $480 for the entire year and you can sign up for a payment plan if you can't pay that whole amount at once. That cost includes everything, there are no hidden charges. I spent that much on books alone when I didn't use this program.
I have to give this program two thumbs up. There are just so many benefits to using CLASS that I can't even list them all here. If you decide to use the system tell them Alicia Bodine sent you!