California gives teenagers a lie-in

SCHOOL STARTING times in America vary from an average of 7.48am in go-getting Mississippi to 8.31am in late-rising Connecticut. According to a survey by the National Centre for Education Statistics in 2017-18, only in two states—Alaska and Connecticut—do schools tend to start after 8.30am, the earliest recommended by a number of medical organisations. That may soon change. On October 13th Gavin Newsom, California’s governor, signed legislation which cuts 2.7m of the state’s schoolchildren some slack, setting a limit on starting times of half past eight for high-schoolers and eight o’clock for middle schoolers, in the hope that pupils will benefit from the extra time in bed.

There is plenty of reason to think they will. Puberty alters circadian rhythms, meaning adolescents are more alert in the afternoon and require more sleep in the morning. A research review by epidemiologists at the Centres for Disease Control finds that later school starting times correspond with improved attendance, less tardiness, less falling asleep in class, better grades and even fewer crashes involving youngsters driving themselves to school. The RAND Corporation estimates that moving to a half-past eight start across the country would boost the economy by more than $80bn within a decade.