Idk if I learned it in school, but I definitely knew about it. I’ve heard “small pox blankets” referenced when discussing what the colonizers did to the indigenous folks in the Americas. Same type of stuff.

I definitely learned about this in school

A lot of history is traditionally passed down orally, and often through the use of symbols signifying universal truths. When oral tradition is interrupted (for example when all your elders die of mysterious causes, or when all your children are sent to factory/reconditioning schools) then history must be re-discovered through archeology - an imperfect method of piecing together clues to reconstruct a best guess for what might’ve happened.