So true. I have often wondered the same thing. But, the public schools will never teach anything that fosters personal responsibility and independence.
The classes I taught had guidelines and specific topics that had to be covered.
In the relatively advanced Algebra II material, interest and interest compounding were required to be taught, so I added some personal finance at that point.
Had to be careful, because all classes were supposed to be kept in sync in the event that students were transferred from one class to another. But a little teacher influence is almost always tolerated if sync is maintained. So I got away with it. Until my contract ran out of special funding and I was released because no one on the staff retired that year. (Obama grant rule.)