Newly retired, at 65 I tutored in an up-scale community's high school. Kids who were not making it...repeat, NOT MAKING IT, in the mainstream math classes, were doing set theory and more that I first saw in science and engineering studies in college. Half of their textbook exercises were in metric units.
Back among the retired folk I knew, I said they were wrong to complain of all young people. The determined complainers had probably grown up in abusive homes so I dealt with them differently.