Dunno how it is in other countries with a recent slave past, but Brazil did an excellent job in erasing both native and African ethnicities in my school years. You never learned about specific native tribes like the Aymore, Tupinamba or Goitacaz, it was always "the natives" and all African slaves were just that, "African slaves", no difference between the ones from current day Mali, Angola or Somalia.

Whenever the books talked about the expeditions into the heartlands, the bandeiras, they rarely or never mentioned local tribes that might've helped them, whether in goodwill, in exchange of something like getting rid of old enemies, or by force.

Another thing that school glossed over was one of the many slave revolts, the Malês Revolt. I vaguely recall that the book said that slaves organized by leaving written notes, but it never mentioned that said notes were written in arabic, because those slaves were from Mali and most of them were muslim, thus they could read and write in arabic. It also never taught us that, after the revolt was quashed, nearly every slave from Mali was sent back to Africa and the city of Salvador, the focus point of the revolt, expelled every muslim and removed every mosque it had.

Man, I could go on for a while, just comparing what I remember being taught in school and all the stuff left out that'd make me really damn interested in paying attention to classes.