As the New York Times reports, “testing results regularly show that math students in the United States are lagging behind those in other industrialized nations. And within the country, there is a persistent racial gap in achievement.” And the traditional approach to math creates the appearance of a conflict between these two real problems: To improve math education, we need to better tailor the difficulty level of math instruction to each student, which happens to some degree when schools offer different levels of math. But when you do that, you often get classes whose racial composition deviates from that of the school as a whole. i.e., The racial gap gets wider. An advanced math class whose composition is racially unbalanced constitutes a visible symptom of educational outcome inequality. And the easiest way to erase such a symptom is to eliminate the advanced math class itself. Yes, if you put everyone in the same math course, some groups will on average get lower grades, but grades are mostly kept secret, whereas class composition is out in the open. Furthermore, putting everyone in the same math course will cause the top students to learn less math than they otherwise would, which is bad for the student, but (perversely) a boon for social justice, since it lowers inequality between groups. For the country as a whole, of course, retarding the math education of the most talented tier of students is catastrophic, as it reduces economic growth and, indirectly, military power. But then again, many of the same progressives who seek to level academic performance also are inclined to downplay the value of economic growth and Western military might. (The richer a country is, the more fossil fuels it consumes.) Moreover, race has become a more or less all-consuming fixation in progressive policy circles, so it seems inevitable that progressive objections to the very idea of separating students into different math classes according to their ability will only become more strenuous over time.
https://quillette.com/2022/02/13/its-time-to-start-treating-high-school-math-like-football/