> That doesn't mean they're not behind, though?
As I asked originally, what does "behind" even mean? It seems to depend crucially on a schedule and expectations. This is why I mentioned social promotion, where students move up in grade simply because a year has passed.
The pandemic has certainly messed up the standard academic schedule, without a doubt. But so what? Are kids irreparably harmed because the standard academic schedule was messed up? I don't think so. Kids were already moving at different educational paces before the pandemic.
I'm not saying it's good that educational quality differs by school district. But this is a socioeconomic problem. There's no "natural human" educational system that the pandemic messed up. When you compare US kids with, say, the great English philosopher John Stuart Mill, we're all way behind. As a kid, J.S. Mill was the beneficiary of an educational experiment almost without equal in history. He was taught Greek at the age of three! Who gets that?