New research shows students have fallen behind in math since the pandemic disrupted school, while most are progressing at a normal pace in reading. The findings released Tuesday by the not-for-profit NWEA show that, compared to last year, students in grades 3-8 scored considerably lower on standardized math tests this fall. English language arts scores were largely the same. But the researchers caution they may be underestimating the pandemic’s impact on minority and economically disadvantaged students. That is because a sizable number of those students were missing this fall when the standardized testing was done.