The Coronavirus Has Made It Obvious. Teenagers Should Start School Later.

School start times are the biggest reason teenagers are often tired. There may have been some justification for it in the past, but not now.

The pandemic has provided us with a unique opportunity to run an experiment in letting teenagers sleep in. It’s happening in my own house. My kids are 18, 16 and almost 14. Their school is being taught mostly asynchronously, through reading or videos. They do have some scheduled meetings and tests, but none begin before 10 a.m., and many are in the afternoon.

My wife and I have removed all restrictions and let them regulate their sleep themselves. The kids seem to be going to bed between midnight and 3 a.m. If they’re not required to be in a morning session, I might see them by lunch.

It is working out amazingly well for all involved. Granted, we are just one family. But there’s overwhelming evidence that kids don’t sleep enough, and a new study makes a compelling case that starting school later would help.

School start times are the biggest reason teenagers don’t get enough sleep. There may have been some justification for it in the past, but not now. Maybe, when in-person schooling resumes, schools should heed the evidence and start later.

On average, most adolescents get fewer than seven hours of sleep a night during the week and eight on weekends. That’s not enough. The natural response is to tell kids to go to bed earlier.

Before the pandemic, however, it was very difficult for them to comply. Many of them had after-school activities, sports, homework and jobs. If we wanted to afford them even a whiff of free time to decompress, it was impossible to move bedtimes much earlier.

More important, they resist earlier sleep. Teenagers are different from adults and younger children. Their circadian rhythms and brain patterns make it hard for them to go to bed earlier.

Letting teenagers sleep later in the morning raises the hackles of most adults. Opposition usually falls into two camps. The first thinks that it won’t make a difference. The second thinks it’s impractical. Both are wrong, especially now.

Let’s start with the first group. Many believe that if we let teenagers wake later, they will just stay up later, getting no benefit over all. Some people also think that permitting them to sleep in would be seen as “giving in” and not preparing them for the real world.

Research shows that this isn’t so. A recent study, published in JAMA Pediatrics, followed more than 450 students over two years in five Minneapolis-area high schools. Students in two schools began starting school about one hour later than the others. The students in all the schools wore actigraphs — a watch-size device worn on the wrist that measures periods of activity and inactivity — to track when they went to sleep, how long they slept and the quality of their sleep.

Those at the schools with a later start time did not go to bed later, in spite of what parents think. They did, however, sleep about 40 minutes more than the kids at the schools that opened earlier. They did so for the entire two-year study period.

“I’ve wondered why as a society we just accept that the majority of our adolescents will go to school every day tired,” said Rachel Widome, an author of the study and an associate professor at the University of Minnesota’s Division of Epidemiology and Community Health.

Confronted by ample evidence (the study is far from the first to argue for later start times, although it’s arguably one of the best), the other group argues that it’s just not feasible to start school later. Many school systems use the same set of buses for schools of all ages — elementary, middle and high school. If we let teenagers start later, elementary schools might need to start earlier. It’s hard to ask young children to wait for the bus really early, outside in the dark.

Many parents work, and pushing back school start times makes it harder for some to get to their jobs on time. After-school activities cause difficulties, too. These must start later if school ends later, potentially complicating afternoon and evening schedules — especially as some teenagers work after school, and families may depend on that money.

There’s even an issue of lighting. Playing or practicing sports later might require (possibly expensive) changes to facilities.

Still, the evidence suggests that the economic benefits outweigh the costs. A study from the RAND Corporation accounted for the drawbacks, including upgrades to infrastructure, additional bus costs and parental rescheduling. Even so, pushing start times back to 8:30 added, on average, more than $9 billion to the economy each year over the first 15 years. That’s largely because students who sleep more do better in school (and later earn more), and are less likely to die in car crashes.

In the best of times, all of the available behavioral, health and economic data argue for later start times. These, however, are not the best of times. With in-person school canceled because of the pandemic, there’s pretty much no excuse left not to let teenagers sleep in.

There’s no car pool for parents to worry about. There are no buses. After-school activities are canceled. Lighting doesn’t matter. All of the arguments are gone.

In my house, I wake up first, because I like to walk for an hour in the neighborhood when no one else is out, before I start work. My wife gets up when I return, as does the dog. Similarly, we let our kids keep a schedule that suits them naturally, which seems to align with a lot of their friends. Everyone seems much happier for it.

Unfortunately, at least in the near term, I don’t really see how this could continue after schools reopen. But it’s not crazy to think that as schools adopt more distance learning and aim for fewer children to be simultaneously present in school, some thought might be paid to alternative schedules that better accommodate teenagers’ natural sleep cycles.

“When you see sleep as a resource that enables well-being of our children, it seems wrong to jump right back into a system that restricts it so severely,” Professor Widome agreed.

In the interim, there’s no reason schools and parents can’t cut teenagers a break. We’re asking them to sacrifice so much already. They’re missing proms and friends and anything even approaching a normal social life. Some, like my oldest, will not have a graduation ceremony this year.

The least we could do is let them sleep.

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