I wish every high school made it mandatory for children to learn how to balance a checkbook and the implications of dept (time value of money).
But really, I think most high schools do teach that. I went to a highschool that was not very good at all, and we spent a fair amount of time on that in math class
http://www.theglobeandmail.com/news/world/how-mobile-phones-...
I'm surprised when someone tells me that are keeping money in a checking or low-interest savings account rather than paying off credit card debt. For whatever reasons they believe this is a common-sensible thing to do.
Because the amount of money you "have" (for spending, emergencies, whatever) is what's in the checking account rather than that plus the remaining credit line on your card, and there's an element of fear/panic about running out (and I guess getting hit with overdraft fees). That fear/panic means that logic suddenly doesn't apply.
That said, we definitely had "checkbook" type lessons in jr. high math class when I was there (early 90s).