Does Later School Start Improve Adolescents’ Sleep and Substance Use? A Quasi-Experimental Study

• In Event: Fostering Students' Development and Learning During Middle School, College, and Emerging Adulthood

Abstract

A later school start time policy has been recommended as a solution to adolescents’ sleep deprivation. We estimated the impacts of later school start times on adolescents’ sleep and substance use by leveraging a natural experiment in which school start time was delayed in some regions in South Korea. The later school start time policy was initially associated with a 20-minute increase in sleep duration and significant reductions in monthly smoking and drinking frequencies. However, the observed increase in sleep duration shrank to 6 minutes, and the reduction in smoking and drinking was attenuated a year after. Our findings suggest that the policy may have positive benefits, but additional efforts may be required to sustain them over time.

Authors

• Jilli Jung, Stanford University

• Andrew Fenelon, University of Minnesota