Part of the home ec curriculum (at least when I took it a long time ago) is personal finances; one thing that we learned in high school (before being able to get a credit card) was that carrying a balance on a credit card is really expensive in the long run.

Exactly. I don't think it warrants it's own class, but it could be integrated into a known framework like ec where the kids are instilled some financial literacy --any literacy in debt.