i think we rely more on college outcome, where the maths and sciences are excellent, than on elementary and secondary education. We also don't have a standard curric throughout our country, whereas many other nations do.
One goal of NCLB was supposed to help standarize curric, so that all children everywhere would supposedly get the same information at the same time. We're a nation of diverse educational values, which is why school system A teaches one thing, while school system B might ignore the same thing that seems so important to school system A.
We're still experimenting.