SAVED BY THE MORNING BELL: SCHOOL START TIME AND TEEN CAR ACCIDENTS

• Published in: Contemporary economic policy 2018-10, Vol.36 (4), p.591-606
• Main Author: Bostwick, Valerie K.
• Format: Article
• Language: English
• Subjects: Accidents; Adolescents; Change agents; Commuting; Deprivation; Economic policy; High schools; Policy making; School districts; School schedules; Secondary schools; Sleep; Sleep deprivation; Teenagers; Youth
• ISSN: 1074-3529; 1465-7287
• DOI: 10.1111/coep.12277

Adolescents today suffer from chronic sleep deprivation due to a combination of biological changes to the circadian clock and early morning school bell times. Many school districts are now considering delaying high school start times to accommodate the sleep schedules of teens. This paper explores whether such policy changes can have an unexpected impact on teen car accident rates. This impact could function both through a direct effect on teen sleep deprivation and indirectly through changes to the driving environment, that is, shifting the time and conditions under which teens commute to school. By focusing on late‐night accidents and employing a difference‐in‐differences strategy using adult drivers as a control group, I find evidence of a persistent sleep deprivation mechanism. A 15‐minute delay in school start time causes a significant decrease in late‐night teen accidents of approximately 23%. However, I also find evidence of an opposing mechanism that is present during the morning commuting hours. A 15‐minute delay in high school start time leads to a 21% increase in morning teen car accidents. (JEL I29, J13, R41)