Is there direction on here for beginning testing as a freshman in high school?

[sewhappy]

If there is, just point me there, please! I've looked around for the past hour and can't find what I need. My oldest will begin hs in the fall and wants to begin to test out of college classes. I'm familiar with college plus, but just don't feel like I need that much hand-holding. The plan is to test out of whatever he can prior to enrolling in TESC or similar. I would like to tweak his hs course of study so he can study, get hs credit, then test, then move on to his next subject. I know that each hs credit will not have a corresponding test, but want to do all we can that way. Where would I begin? Does it matter?

Thanks!