The lost foundations: Projected trajectories linking COVID-19–related school readiness losses to later academic achievement

This study examined whether developmental losses due to the COVID-19 pandemic predicted later academic performance. Participants were 3,760 children enrolled in public preschools in Uruguay, assessed with the Child Development Inventory at ages 4 and 5 (2019-2020) and later with the national third-grade assessment (2023). The sample was 51.5% female, 48.5% male, 83.6% White, with the remainder identifying as other racial/ethnic groups, mean age 8.53 years (SD = 0.50). Simulating what would have occurred if the pandemic had not affected development, results suggested that children would have achieved higher mathematics and reading scores if their cognitive and motor development had not been affected. Effects were small (<0.10 SD) but statistically significant, with no evidence of widening socioeconomic gaps.