If you went to high school in the US, you may remember early morning extracurricular activities, sleeping through the first bout of algebra, or hazy study sessions late at night (unlike other wide awake “study sessions” we call our parents). told we were). As an adult, you may be wondering if there’s a better time to explore Shakespeare than at 8 a.m., or to extend a Taylor series right after you collapse in your chair, half asleep. after your sunrise bus ride.
As it turns out, early school hours for high schools in the US are built on shaky scientific foundations, as journalist and parent Lisa Lewis points out in her new book: The sleep-deprived teenager. She explains why high schools in the US tend to start early, the science behind why that’s bad for kids, and how late school hours can benefit not only teens, but, well… everyone. Perhaps most importantly, she provides an introduction to advocating for change in your community.
The wheels of the bus go round and round
Our early start times are a bit of a historical coincidence. In the first half of the 20th century, schools were mostly small and local – most students could walk. Lewis points out that in 1950 there were still 60,000 one-room schools across the country. By 1960, that number had dwindled to about 20,000.
According to Lewis, that trend accelerated because US authorities feared that education — especially in science and mathematics — was lagging behind that of its nemesis, the Soviet Union. She describes how a 1959 report written by James Bryant Conant, a chemist and retired president of Harvard University, recommended that high schools graduation class sizes of at least 100 – a far cry from small local school buildings. The consolidation of the school, which had already begun, accelerated. Neighborhood schools continued to close. And the yellow school bus was locked in a trajectory to its current iconic status.
To minimize bus transportation costs, Lewis describes how many districts staggered school start times so that they could use the same buses to transport elementary, middle, and high school students. At the time, there was a societal consensus that teens needed less sleep than young people, so high schools got the earliest seats.
And the science says…
In the 1950s and 1960s, scientists had yet to delve into teenage sleep. But that began to change in the 1970s, starting with the Stanford Summer Sleep Camp experiment led by then-doctoral student Mary Carskadon, now a professor of psychiatry and human behavior at Brown University. Lewis takes readers through the highlights of the multi-year study, in which scientists tracked sleep patterns and metrics ranging from brain wave monitoring to cognitive tests on the same children for 10 years, from 1976 to 1985.
Surprising results came from this first look at teenage sleep. For example, adolescents needed as much or even more sleep than younger children. On average, all children in the study, regardless of age, slept 9.25 hours a night. Subsequent studies have shown that the ideal amount of sleep for teens is between 8 and 10 hours a night. Still, Lewis reports that in 2019, only 22 percent of high school students reported being quiet for at least eight hours, according to the CDC.
Another key finding from the Stanford Summer Sleep Camp experiment was that older children had a lot of energy later in the day. Subsequent studies showed that when children enter puberty, their brains slow down the release of melatonin, the hormone that makes us sleepy. For teens, melatonin rises later in the night and falls later in the morning, altering their circadian rhythm. High school students’ tendency to stay up late and sleep off in the morning isn’t necessarily laziness or defiance — it’s biological.
But here we are, decades later, with an average school start time in 2017 starting at 8 a.m. and 40 percent of schools even earlier. This is a dramatic change from a century ago, when high schools in the eastern US started at 9 a.m., Lewis notes.
Why haven’t schools adapted to this influx of new information? Well, some schools do. Lewis runs through several examples throughout the book, showing schools that have had positive impacts in abundance, even in the age of smartphones and social media.
Lewis describes a study, published in 2018, in which students slept an extra 34 minutes each school night when their Seattle district shifted the start time to 8:45 a.m. That may not seem like much, but many students and families gave positive feedback, as did the teachers, one of whom described the morning atmosphere as ‘cheerful’ – an adjective that many of us may find inscrutable for the first period.
