I will also add that the US high school educational standard does not require maths education beyond Algebra I and Geometry. Since math "isn't cool" most students do not study beyond the bare minimum in the USA.

It is only at courses beyond the basics, beginning with Algebra II where subjects such as compound interest are taught and the foundation is laid for how to manage personal finance. The sad truth though is that most students cannot pass Algebra II because their basic math foundation is too weak at the elementary level. There is too much "feel good" and not enough discipline required to enforce precision and accuracy that is mandatory at the higher academic levels.

It is also why so many americans get into trouble with credit card and mortgage debt. They simply don't understand their relationship with the financial contract they have gotten themselves into.