Final answer:
Black delegates during Reconstruction were instrumental in establishing public school systems in Southern states as part of revising state constitutions.
Step-by-step explanation:
During the period of Congressional Reconstruction following the Civil War, black delegates made significant contributions to revising state constitutions in the southern states. One major accomplishment they achieved was the establishment of public school systems.
Prior to this, public schools were virtually non-existent in the South, but by the end of Reconstruction, every Southern state had established a public school system. Additionally, these revised constitutions expanded rights and made strides towards more egalitarian societies, including extending suffrage and improving conditions for the poor and disadvantaged.