I went to school in the south, and we did learn about this in school, but not necessarily in class.
My district was still litigating its original Brown v. Board follow-on lawsuit from the 1950s in the twenty-first century. To get released from the lawsuit, the district had to show that the racial composition at each school matched the overall average for the whole district within 10 percentage points.
That meant that each school needed to be 75-85% black enrollment, in a city that was 54% black overall. Where did all those white students go? They went to private religious schools and to the suburbs. This was obvious to any kid when you went to the sporting events.