I was homeschooled K-12. Even 15 years ago, my parents would say that they were like general contractors for my education. And it is really is true. I had a mix of co-op, community college, online, self-study, and parent-guided study for all my courses. This was more so for highschool and less so for primary or grade school, which was mostly directly taught by my mother. And as others have said, homeschooling is very, very time efficient. IIRC, during grade school I was done by lunch time (maybe one or two smaller things required).