considering scm

I have been hs for 5 years and have heard about charlotte mason method quite a few times.   I am really considering using it for this upcoming 2010-11 school year.  Forgive me if this question has been asked 100 times before…but how do I begin?   Usually curriculum is a set thing-you buy the book and teach from it. SCM has many many choices.   For instance I clicked on math..and was taken to a page with several options for teaching middle school math.    How will I know if I meet requirements of high school?  

my ds are 12 and 16…son 13.   I now teach with an assortment of  books, but would like to have a better plan for next year.  

Any suggestions as to how yall got started with CM and how it worked out.   What you tried and what worked? 

thanks ever so much for replies.