The average level might probably decline (and this is the world tendency), but the level of the best students has not. There may be a lot of reasons. 1) For example, an officer in some department of education might decide that deep studying of math can be stressful for middle school students 2) Is the salary of a math teacher comparable with that of an engineer? Which quality of math teachers do you expect at an average school? 3) One per-cent of middle school students continue their careers in academia and hi-tech. Number of mid-school students that are good in math is not very high, but much more than one per-cent. One can say that the job market does not require profound knowledge of math from all middle school students