There are a myriad of old textbooks on the internet for free.
I really don't see what is so complicated about homeschooling, and why a course plan is necessary.
Once a child can read, calculate, and write with adequate penmanship, there are no serious obstacles to advancement.
whether it's history, geography, geology, biology, astonomy, chemistry, physics, algebra, geometry, calculus, grammar, composition and literature.
Really there is nothing to it.
There are tests of basic skills that can be administered to see if the child is progressing at a good pace.
I really don't see what's so complicated.
It's not as though elementary school teachers are more knowledgeable than the average trad parent.