I can answer this with one symbol - $.
I'm in my late 30's and remember how they eliminated shop, home economics (which, to be honest, I'm totally fine with), and a number of "life skills" type programs at my high school while I was still attending. Budget cuts were the name of the game in the early 2000's and we're still dealing with the consequences of those in our nations schools today. Tax cuts sound great in theory, but they had devastating consequences for many of our nations public schools.
It didn't used to be this way for my parents and my parents parents, but unfortunately it's the way it is now. The only way it could change is if we rethink how we fund schools and what our priorities are in this ever changing world.