Dawn, I'm right there with you.

It can be very frightening to face the higher grade levels and to know that if they were in a traditional school setting they would be getting things we can't possibly offer (advanced labs for science is a biggie for me). We go back and forth between private school, dual credit at the local community college, and moving to be in a better district. And honestly, relinquishing the time is hard, but when #1 son got his full curriculum in a box this past year, I was amazed at my sense of relief. Spreading yourself out between 3 isn't easy and the "Momma, can you help me?" always seems to happen at once.
People here speak highly of the co-ops. I don't use them for various reasons, the most of which is that my accountability association requires that I teach 51% of his classes.
PM me any time you need or want to talk.