Scientifically Speaking | No, the kids aren't alright

The science is clear – start schools later in the day because that's when their cognitive performance is better

I hated getting up early in the morning to go to school. Now, my son hates it. Decades separate us. Despite the growing scientific literature that forcing children and teenagers to get up in the morning might be detrimental to their health and wellbeing, many schools still start at 7 or 8 A.M. As the saying goes, ‘plus ça change, plus c'est la même chose’. (The more things change, the more they stay the same).

When did forcing children to get up early become a virtuous ritual?(Representative Image Unsplash)

When did forcing children to get up early become a virtuous ritual? Perhaps it was with the spread of aphorisms like “early to bed and early to rise…” or in my household, Chanakya’s shlokas. Perhaps it was the notion that children perform best on activities early in the morning.

But change may be coming in some places, even if it is long overdue. I was heartened to learn from an Associated Press (AP) news report that in the United States, some schools are starting later in the day “to improve kids’ mental health”.

But, why do so many schools start so early in the first place?

In the AP  news story dated May 8, Orfeu Buxton, the director of the Sleep, Health & Society Collaboratory at Penn State University notes that the reason is “lost to the sands of history” adding that “everything is baked into that: “traffic light patterns, bus schedules and adults’ work.”

What is not baked into early school is the actual biology of children. For much of history, children and teenagers were thought of as small versions of adults without much consideration of their unique metabolism and development. Scientific studies had not progressed to the point that individual and population differences were well known either or that we understood the biological links between the circadian system — our internal, daily cycle or “body clock” —  and health.

We now know that every adult has their own “chronotype” which determines their preference for being a “morning person” or an “evening person”. People have varying optimal times for different activities too. But this chronotype isn’t a fixed inherited characteristic. Age is one of the factors that determine chronotype.

This is the critical point that’s missed when we force children and teenagers to conform to adult schedules. Groundbreaking research by Lynne Hasher’s team at the University of Toronto has shown that on average, adults (and especially those over the age of 50) do better in cognitive tests at 8 or 9 AM in the morning compared to 4 or 5 PM in the afternoon. Teenagers' performances, in contrast, are poorer in the morning but get better during the day.

In their book Circadian Rhythms, University of Oxford neuroscientist Russell Grant Foster and biologist Leon Kreitzman gets to the heart of the matter, writing that “senior teachers in their fifties will generally be at their best the first thing in the morning, but their students will invariably be ill-prepared by their circadian system to learn…The senior teachers and not the students determine the timetable and the tacit assumption for well over a century has been that students are most alert in the morning and the most important and intellectually demanding subjects should naturally be taught during this time. This assumption is wrong.”

To make the problem relatable to adults, Foster and Kreitzman tell us that teenagers suffer from a “social jetlag” of two hours and that asking a teenager to wake up at 7 AM in the morning is like asking a 50-year-to get up at 5 AM. Though there’s variation among people in a population, young adults benefit from staying in bed early in the morning, while adults in their fifties and sixties are early risers; their peak cognitive performance often occurs mid-morning.

Not only are teenagers without “social jetlag” happier, but studies indicate they are healthier too. Each hour of “social jetlag” is linked to a 30 percent greater risk of being overweight or obese.

Historically, I suspect that there were economic reasons for favouring an early start. Adults (including teachers) went to work in the morning and so it made sense for school to start early. School times that corresponded to work times also reduced the need for extra childcare. I heard this concern expressed explicitly many times by caregivers when in-person instruction resumed after the first two years of the pandemic.

Some critics of a later start also point out that instructional time in school may be reduced. But a later start can also lead to a later end time. More to the point, why do total hours matter anyway? In every other facet of life in the modern era we prioritise improving creativity, productivity, and competitiveness over simply clocking in bulk hours.

All said, I recognise that changing school hours is a contentious topic with practical consequences. I’m not arguing that concerns of parents or teachers should be dismissed just as concerns of children have been for so long. But we cannot dismiss the biology underpinning children’s performance. After all, who is school actually for anyway?

Anirban Mahapatra is a scientist by training and the author of a book on Covid-19. The views expressed are personal.