School Reopenings During COVID-19 Linked to Significant Improvements in Children's Mental Health

The COVID-19 pandemic created unprecedented disruptions to children's lives, with school closures affecting millions of students worldwide. While much attention focused on infection control and academic learning loss, a crucial aspect of the pandemic's impact has been children's mental health. New research provides compelling evidence about one of the most effective interventions for supporting children's emotional wellbeing during public health emergencies: returning to in-person schooling.

A landmark study published in Epidemiology on December 8, 2025, by researchers from Harvard T.H. Chan School of Public Health and collaborating institutions offers one of the most comprehensive analyses to date of how school reopenings affected children's mental health. The research examined health diagnoses and spending information for 185,735 children aged five to 18 across 24 counties and 224 school districts in California from March 2020 through June 2021. This extensive dataset, drawn from the Healthcare Integrated Research Database and California Department of Education records, provides robust evidence about the relationship between school attendance and mental health outcomes.

The Impact of School Reopenings on Mental Health Diagnoses

The study documented a clear pattern: children who returned to in-person school were substantially less likely to receive new mental health diagnoses than their peers whose schools remained closed. By the ninth month after reopening, the chance of being diagnosed with a mental health condition had dropped by 43% compared with the period before reopening. This significant reduction encompassed multiple conditions, including anxiety, depression, and attention-deficit/hyperactivity disorder (ADHD).

While the pandemic saw an overall increase in mental health diagnoses among children—rising from 2.8% to 3.5%—the reopening of schools acted as a powerful countermeasure. The research team's analysis revealed that the benefits of returning to school were not limited to just one type of mental health condition but represented a broad improvement across multiple diagnostic categories. This suggests that the school environment provides comprehensive support that addresses various aspects of children's emotional and psychological wellbeing.

Healthcare Spending Reductions

The improvements in mental health translated directly into reduced healthcare costs. Nine months after schools reopened, non-drug medical spending related to mental health was 11% lower, spending on psychiatric medications was 8% lower, and spending on ADHD-specific medications was 5% lower. These reductions in healthcare spending reflect not only improved mental health outcomes but also significant economic benefits for families and healthcare systems.

The connection between school attendance and reduced healthcare spending highlights how educational environments serve as preventive health settings. By providing structure, social interaction, and access to support services, schools may help mitigate the need for more intensive and costly mental health interventions later. This finding has important implications for healthcare policy and education funding decisions, particularly during public health emergencies when resources are often strained.

Gender Differences in Response to School Reopenings

One of the study's most notable findings was the differential impact on girls and boys. Girls showed greater improvements in mental health outcomes than boys over the same period following school reopenings. This gender difference suggests that certain aspects of the school environment may be particularly beneficial for girls' emotional wellbeing.

The research team, led by senior author Rita Hamad, professor of social epidemiology and public policy, noted that this finding aligns with previous research showing that girls may be more vulnerable to certain mental health challenges during periods of social isolation. The structured environment of school, along with peer interactions and access to supportive adults, appears to provide particularly important protective factors for girls' mental health. This insight could help inform more targeted support strategies for different student populations during future disruptions to normal schooling.

Why School Closures Affected Children's Mental Health

The research team identified several mechanisms through which school closures may have negatively impacted children's mental health. These include limited social interaction with peers, disrupted sleep routines, increased screen time, poorer dietary patterns, academic struggles, family stress linked to economic hardship or increased time at home, and reduced access to school-based mental health services. Each of these factors represents a pathway through which the absence of school structure and support could contribute to worsening mental health outcomes.

Schools provide more than just academic instruction—they offer consistent routines, social connections with peers and adults, physical activity opportunities, nutritional support through meal programs, and access to counseling and mental health services. When these supports were removed during school closures, children lost multiple protective factors simultaneously. The study's findings suggest that the cumulative effect of these losses was substantial, contributing to the documented increases in mental health diagnoses during the pandemic.

Policy Implications and Future Directions

The study's findings have significant implications for public health policy, particularly regarding how to balance infection control with children's wellbeing during future emergencies. As Professor Hamad stated, "Our results provide solid evidence to parents, educators, and policymakers that in-person school plays a crucial role in kids' well-being. The findings offer lessons for future public health emergencies and provide insight into why mental health worsened for children during the pandemic."

The research suggests that policies should focus not only on infection control but also on maintaining the mental wellbeing of children by recognizing schools as critical components of their support system. This includes ensuring safe school reopenings during public health emergencies and providing adequate resources for school-based mental health services. The study also highlights the need for more research exploring how school reopening influenced children in marginalized communities, where the impact may have been even more significant.

The study received funding from the National Institutes of Health (grant U01MH129968) and represents an important contribution to understanding the complex relationship between educational environments and children's mental health. As communities continue to navigate the aftermath of the pandemic and prepare for future public health challenges, this research provides valuable evidence about the importance of maintaining access to in-person schooling whenever safely possible.