Agree we'll be discovering the effects of covid for many years to come. And again, I'm not saying that covid's cognitive loss effects have not played any role in lower test scores. I'm sure that they have. But I don't think we can rule out remote learning as a factor.

Think of education like building a tower out of bricks. Each year of school is a new layer of bricks. Remote learning lays down some, but not all, of a layer of bricks. But we pushed the kids onward to the next school year anyway and started building a new layer of bricks, despite the previous layer being unfinished.

A freshman in high school during 2020 had an unfinished layer 9 and unfinished layer 10. In their junior year, in-person learning resumed full time and started building layer 11. Their teacher even tried catching them up on the missed material from the previous years, shoving some bricks into layers 9 and 10 wherever they could.

Compare that freshman to a student who is 1 year older. They were a sophomore in 2020. They have a finished layer 9, an unfinished layer 10, and an unfinished layer 11.

Both take the ACT at the end of their junior year. If we measure both towers at that point in time, which do you expect to be taller?

Education is sequential. Missing knowledge in an earlier grade will mean that the student will struggle more to catch up in the future. I don't think it's reasonable to expect test scores to improve just because in-person learning has resumed. There is only so much catching up that students and teachers can do, especially when the foundational layers of knowledge are spotty at best.