In fact, the "mathematics education" you mentioned belongs to the theory of mathematics teaching. Now Nanjing Normal University has a new department called Teachers College, and mathematics education should be managed by Teachers College. There are basic mathematics and pedagogy courses in the study curriculum, but the latter is emphasized, mainly some educational research. To put it bluntly, it is to study how to be a math teacher and teach math well. Every subject has this teaching theory. Every year, there are arrangements for attending classes, teaching and researching educational topics in various schools, and there are also opportunities for exchanges abroad. As far as I know, some students of China's teaching theory went to the United States as exchange students. I will be a math teacher after graduation.