Ontario used to have that system, when I was in high school; the choice was totally up to the student which level of challenge they wanted - Basic, (Regular - had a name, but I can't remember it) and Advanced. Some courses were only one or the other, but those were usually the optional courses you could take for your credits (Typing was a Basic business credit, and World Religions was an Advanced history credit). If a kid had trouble at one difficulty level, the teachers and counsellor might take him aside and suggest they drop down to Basic, but they couldn't force him to do so. Similarly, though, if someone seemed to be breezing through an easy course, they'd similarly suggest switching up to a higher difficulty.

No one shamed anyone for anything they chose, because everyone took a mix of difficulties; it was actually a good way to question yourself. But I guess we can't have that in the modern age. They got rid of this system about a year after I left. This was the 1980s, mind. I thought I heard them talking about bringing it back, though.

Meanwhile, I see this YouTube thing screeching about the "horror" of an old experiment where researcher parents tried raising a chimp alongside their own son to see if the chimp would adopt human behaviours from being exposed to and playing with the boy; turns out the boy started taking on chimp-like behaviours. (Probably because being human sucks so much.) Now that alone should tell people why you don't mix normal kids in with retards - you just get a whole pack of kids who act like retards.

Humans are like one big crab bucket. They like to jeer at and drag down those they see as their "betters", while at the same time stomping the fuck out of those they see as their "lessers" so that they never have a chance to shine in their own way.