> Childhood nutrition, single parent households, health of mother during pregnancy, culture/respect towards education as a virtue in the community and household, education level of parents and the time they have to play and talk with their kids.

I'm not American, and I don't claim to know the environment and the issues people face there, or their root causes. I may not be fully understanding the extent of nutritional differences or family dynamics.

I am, however, absolutely certain that affluence feeds affluence and that misfortune feeds misfortune, on average. Even if you had all of the above equal except for the education levels and socio-economic status of the children's parents, you'd end up with statistically different outcomes.

I live in a fairly egalitarian country, and if I remember correctly, there's an average income gap of ~30 percent or so between people whose parents were in the highest quartile in income and those who were in the lowest quartile. While ethnicity may play some role in the statistical gap nowadays, I don't think it explains the statistical difference; ethnic minorities are disadvantaged here but they make up a small enough minority that I expect the bulk of the difference to be simply due to socio-economic differences within the same ethnic group.

Basically, if your parents and their social in-group got highly educated, I believe you perceive that as the norm. If they didn't, it's not as likely that you do.

Add in some practical stuff such as whether your parents can afford to finance or support your education, and the gap's already there. The rest just amplifies it.

Sure, physical health, nutrition etc. can have an effect, and they certainly do if the differences are great enough. I'm sure ethnicity or race has an effect, sometimes due to racism, and sometimes because people perceive their own opportunities or expectations differently depending on social roles, and for various other sociological dynamics. The latter is true even if you remove ethnicity or race from the equation. Racial stereotypes and images probably emphasize things but I don't think you can pin it all on that.

Considering how much worse off African Americans are socio-economically, on average, than white Americans, it's a no-brainer that their kids end up worse off on average as well. I'm not saying you should just shrug and accept that, and I'm sure actual racism exists as well, but the point is that some of it would happen even without racism, either overt or covert, or any "structural racism" that could include a whole spectrum of things.

That means any real solution is going to be hard and slow, unfortunately. Changing the subject matter in the name of equity really doesn't sound like one.

> I believe most proponents of "math equity" actually know all this, and are just maliciously virtue signalling either because they're jealous that their own kids aren't doing well, or for social credit.

It could also be that people take an easy non-solution in preference to working towards improvements and solutions that could take time, great patience, tolerance of morally and socially undesirable situations (one might have to accept that you can't achieve perfect equity, or at least not quickly, and be able to withstand social judgement for that), and are all around a lot harder to accomplish.