What I did years ago, it has been damaged and destroyed now, but next bonus going to do again.
What we did is go to a used book and text book place and bought a complete abbeca books and lesson books set of English, Math, the Sciences 1-12th grade, plus a few early primers for history and other topics. One set, figured if I ever had to teach my kids (now my grand kids) in Badtimes, I could use that as fall back information once they had the basics and then the practical lessons. But that is not counting you personal library and that includes encyclopedias and dictionaries, and other topics that interest me. What else can be found. I have a few old maps and one old globe that show the world as it was when I grew up to help explain history. It is a far from perfect system, but it should get them the basics. Practical lessons if and when it comes to that point will be more important, than higher education, jmo