The COVID-19 pandemic has been a seismic and ongoing disruption to K–12 schooling. Using test scores from 5.4 million U.S. students in Grades 3–8, we tracked changes in math and reading achievement across the first 2 years of the pandemic. Average math test scores in the fall of 2021 in Grades 3–8 were .20–.27 standard deviation (SD) lower relative to same-grade peers in the fall of 2019, while reading test scores decreased by .09–.18 SD. Achievement gaps between students in low-poverty and high-poverty elementary schools grew by .10–.20 SD, primarily during the 2020–2021 school year. Achievement disparities by student race/ethnicity also widened substantively. Observed declines are more substantial than during other recent school disruptions, such as those due to natural disasters.

The schooling disruptions due to the COVID-19 pandemic continue to reverberate across the K-12 educational system more than a year after schools closed for in-person instruction. In this study, we examined the aftermath of these disruptions by modeling student achievement trends prior to and during the pandemic, with particular focus on growth in 2020-2021. The data included test scores from 4.9 million U.S. students in Grades 3 through 8. Although the average student demonstrated positive gains in math and reading during the 2020-2021 school year, students were still behind typical (prepandemic) averages by spring 2021 (0.16 to 0.26 standard deviations behind in math and 0.06 to 0.11 standard deviations behind in reading). Furthermore, growth in math was more variable than in prior years, and much of the gains occurred among initially high-performing students pulling further ahead. Findings support the theory that the pandemic left students behind academically across the board while also worsening existing educational inequities.

The COVID-19 pandemic has been an unprecedented disruption in students’ academic development. Using reading test scores from 5 million U.S. students in grades 3–8, we tracked changes in achievement across the first two years of the pandemic. Average fall 2021 reading test scores in grades 3–8 were .09 to .17 standard deviations lower relative to same-grade peers in fall 2019, with the largest impacts in grades 3–5. Students of color attending high-poverty elementary schools saw the largest test score declines in reading. Our results suggest that many upper elementary students are at-risk for reading difficulties and will need targeted supports to build and strengthen foundational reading skills. Supplementary Information The online version contains supplementary material available at 10.1007/s11145-022-10345-8.