Do all the countries you advertise as having taken the math/science testing (and coming in with higher scores than the USA) require all children to go to school as we do? Is the testing done (in all ...
Unfortunately, there is virtually no standardization of tests between nations.
For example, Indian matnematics at their "graduate" level seldom contemplates more than what our students complete in high school: integral, differential, physics, chemistry, and microeconomics.
Indian students quite often find that they must take remedial math and science before they enter their freshman studies. British students make it virtually a certainty. Mexican students accepted at American universities are so far below minimums that I hesitate to mention their scores.
One reason they appear so bright is that they get nearly a year of instruction -- by rote -- in SAT and PSAT. They have the answers memorized but not the rationale nor have they done the work that leads up to college.
We do not commit these unethical practices. Our students have actually learned what they need to know before they apply to universities.
I hate to say it, but there are lots of cheats in this world. They seem to score higher on entrance exams, but they do not have it where it counts.