It’s really basic social studies in the “world history and cultures” category, I would expect them to learn it in high school. The US had a literal race based

It’s really basic social studies in the “world history and cultures” category, I would expect them to learn it in high school. The US had a literal race based “caste-like” system for much of its history. In the South this didn’t end until the 60s, and many people alive today were alive when it was still strictly enforced.