Economic reasons aside, I think Soviet educators also believe that rigorous and challenging training will realize the greatest potential of students. The top st

Economic reasons aside, I think Soviet educators also believe that rigorous and challenging training will realize the greatest potential of students. The top students are self-driven and usually get the best resources anyway. It is the majority middle that need most rigorous and challenging training to realize their full potential. Unfortunately, US educators in K-12 decided to move in the opposite direction. David Klein's writing told appalling and sad stories of how National Council of Teachers of Mathematics (NTCM) won over the course of last 100 years: - A quarter century of US 'math wars' and political partisanship - A Brief History of American K-12 Mathematics Education in the 20th Century By the way, US's upper-level college course and post-graduate textbooks are hardcore too. If you don't believe me, go check out the Graduate Texts in Mathematics.