I was hoping you would get more responses.
I really like what I have seen of Core Knowledge. If there were a homeschool curriculum that implemented Core Knowledge, I would consider using it. Maybe someone needs to write one?
I refer to the "What you X grader Needs to Know" books, but I know that is really just a supplement to the program. I know the Core Knowledge website has a page or two or using it for homeschooling, and I have seen Core Knowledge lesson plans around the internet.