The Benefits of Delaying School Start Times: Where Are We Now?

by Martin Reed Patient Advocate

Sleep experts and medical professionals have long argued that early school start times are making it difficult for kids to reach their academic potential and may even be harming their health.

As a result, some schools have adjusted their schedules so school begins later in the day. A study out of Yale University set out to determine the results of these later start times.

The problem with early school start times

As children progress through puberty, their circadian rhythms begin to favor a delayed sleep phase that prefers late morning and late day activities.

This is obviously incompatible with the usual school start times in the United States of around 8 a.m.

The impact on children is sleep deprivation and daytime sleepiness, which has a negative effect on learning and overall health.

Analyzing the effect of later school start times

Over the past decade or so, a number of schools have started to delay school start times so they're more in line with a child's natural circadian rhythm.

In the Yale University study, researchers conducted a systematic review of six studies that examined the impact of delayed school start times. The reviewed studies involved schools and students in the United States, China, Israel, and Norway.

The effect of delayed school start time on overall sleep duratioll six studies reviewed found that delayed school start times led to students getting more weekday sleep. Additional sleep time ranged from 25 to 77 minutes.

That means that over a school week, some students were getting more than six hours of additional sleep after their school delayed start times.

The effect of delayed school start times on overall health

One study found visits to the health clinic to rest fell from 69 to 30 visits after school start times were delayed, and two studies found significant decreases in depression scores.

The effect of delayed school start times on academic achievement

Only two of the six studies evaluated the effect of later school start times on academic achievement. Neither found a significant difference in self-reported grades — however, they did find significantly fewer cases of tardiness and falling asleep in class.

One study found significant improvements in attention levels after start times were delayed, and another reported improvements in reaction times. The latter is of particular importance when we consider the prevalence of drowsy-driving among teen drivers.


This review found that delaying middle and high school start times to 8:30 a.m. or later (as recommended by the American Academy of Pediatrics) may help:

  • increase overall sleep time

  • reduce daytime sleepiness

  • improve health and academic outcomes

How to influence change

Unfortunately, even though many schools recognize the benefits of later start times, school districts still struggle to make the change due to the financial and strategic barriers involved.

It would appear it's worth the effort though.

_If you want to get involved, you can petition Congress and/or sign local, regional, or state petitions at Start School Later, a 501(c)(3) non-profit organization that is campaigning to make “school start times compatible with health, safety, education, and equity.”ee More Helpful Articles:

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Martin is the creator of Insomnia Land’s free sleep training for insomnia. His online course uses CBT for insomnia techniques to help participants fall asleep and stay asleep. More than 4,000 insomniacs have completed his course and 97 percent of graduates say they would recommend it to a friend.

Martin Reed
Meet Our Writer
Martin Reed

Martin is the creator of Insomnia Coach, an eight-week course that combines online sleep education with individual sleep coaching. His course helps clients improve their sleep so they can enjoy a better life with more energy and start each day feeling happy, healthy, rested, and refreshed. Martin also runs a free sleep training course that has helped over 5,000 insomniacs. He holds a master’s degree in health and wellness education and studied clinical sleep health at the University of Delaware.