Public Education Failure

Just approximately 50% of the population attended public schools in the South, compared to around 90% in the North, because most of the South was more rural than the North and children would be needed for farm work from an early age. Huge wealth inequality, as stated in the first paragraph, made matters worse because it encouraged elites to take their kids to private schools, further depriving schools in sparsely populated areas of funding.

That's not to suggest that measures weren't made to counter that. In the decades prior to the Civil War, there were concerted and momentarily successful grassroots initiatives to increase access to public education in Louisiana, Mississippi, and Alabama, according to Sarah Hyde's Schooling in the Antebellum South. However, economic catastrophes like the Panic of 1837 foiled the efforts. That was a structural fault in a society where income disparity was so pervasive.