If you ever learned about slavery in the lead up to the U. S. civil war, I’d be surprised if it wasn’t taught (whether or not you remember it is another matter). It was a pretty momentous decision widely recognized as one of the worst in US History. It stated at its basic level in a opinion written by the chief justice (Taney) that Black people could never be citizens of the United States and that Congress had no authority to stop or limit the spread of slavery into American territories.

I guess if you were in a school where you learned the “War of Northern Aggression” was over states rights it’s possible.