> So many kids learn 4 years of algebra without having the slightest clue that this all is building to something called "Calculus" that they don't understand what it is.

That specifically at least could be improved greatly by just reworking classes to include plenty of hands-on practical application so it’s not so abstract. The pervasive thought during that period of my life was, “why am I learning this” and nobody wanted to bother answering except with the non-answer, “you might need it someday.”