A literal Flat Earther is complaining about other people's math scores.
The author of your article, "Mike Antonucci", is a right-wing military guy with zero background in education. The website he's writing for "The 74", is a Republican-led lobbying effort to defund public education funded by Betsy DeVos (Trump's ultra-rich and ultra-incompetent Secretary of Education), the Walton family, and other right-wing billionaires.
The I Promise school specifically admitted students who were struggling and far behind grade standards. Some classes had close to 50% of the kids on IEPs. Before 2020, the state of Ohio gave the I Promise school a grade of "A" for academic progress - while their students weren't up to grade standard yet, they were improving faster than the average school and more than meeting their progress targets.
Then the pandemic hit, schools closed, and test scores plummeted everywhere. For the kids at the I Promise school, who often had the most difficult home backgrounds, school-from-home likely hit them the worse. And that's the most obvious explanation for why the progress they showed before 2020 didn't hold.
But you don't care about that, because I've never seen you do anything, ever on this forum besides push conspiracy theories, right-wing misinformation, and hate on LeBron.