["Journal of School Health, Volume 96, Issue 8, August 2026. ", "\nABSTRACT\n\nBackground\nThe COVID‐19 pandemic disrupted schooling worldwide. While there is evidence of declines in academic performance, the links between early vulnerabilities in school readiness, learning difficulties, and lifestyle changes during the pandemic and their impact on postcrisis academic achievement are not well understood.\n\nMethods\nThis longitudinal study followed 3871 children across three time points over 6 years (50.3% boys). In 2017, teachers assessed children's school readiness at kindergarten. In 2021, parents assessed the impact of COVID‐19 on their child's learning difficulties and lifestyle changes. In 2022, teachers assessed children's academic achievement.\n\nResults\nStructural equation modeling showed that children with school readiness vulnerabilities experienced greater learning difficulties during the pandemic, but not significantly greater lifestyle disruptions. Learning difficulties partially mediated the association between school readiness vulnerabilities and lower postcrisis academic achievement. Analyses were adjusted for child sex, age, native language, and cumulative socioeconomic risk.\n\nImplications for School Health Policy, Practice, and Equity\nSupport systems should monitor learning difficulties that emerge during periods of educational disruption and not rely solely on preexisting indicators of vulnerability.\n\nConclusion\nLearning difficulties during the pandemic emerged as a distinct predictor of later academic achievement, emphasizing the need for timely educational support during periods of disruption.\n"]