A later school start time could easily be on every teenager’s wishlist. They just never seem to have enough sleep, but they also don’t listen if parents tell them to go to bed early. As it turns out, teens’ circadian rhythm shifts as they become adolescents, so they’ll naturally feel the need to go to bed after 11 pm and wake up later than when they were children. On top of that, they still need an average of about 9 hours of sleep per night. Count in all extracurricular activities, jobs, sports, and season it with late-night technology use and early school start times and you have a recipe for a chronically sleep-deprived young person.
Constant sleep deprivation increases the risk of anxiety and depression, illnesses, obesity, and poor memory and learning skills. This is so ingrained in the system that it seems almost impossible to change; fortunately, the Seattle School District has broken the ice and shown what just slightly longer sleep does to adolescents in a real-life setting.
Study: Later school beneficial for learning, performance, and physical presence at school
According to the Seattle (WA) study, delaying school time resulted in increasing the average sleep by 34 minutes per night and improving attendance and students’ grades.
They shifted school start time by only 55 minutes (from 7:50 to 8:45 am) most of which students spent sleeping. This change also decreased social jet lag. Social jet lag is what often happens with school kids and workers. As they go to bed later and sleep in during the weekend, they suffer more on Mondays when it’s time to get back in rhythm with the rest of society.
The study also noted that, as a result of the late school start time, students could start going to bed later and be exposed to light until a later time at night. This would be counter-effective because strong lights, LED lights, and blue screen lights delay melatonin release which in turn delays sleep time and the circadian clock.
If later school time were to be combined with less late-night exposure to blue light and more good sleep habits, the average teen sleep time would probably be even longer.
One out of two surveyed schools showed a large decrease in absence and tardiness, while the second one had no changes for this parameter. The big improvement happened in economically disadvantaged schools that have more ethnic minority students.
Sleep has increased from 6h 50min to 7h 24min, which is still frighteningly shorter than what teens need for healthy mental and physical development; but it was enough to increase their academic performance, reduce sleepiness, and help their inner clock align with wider society.
Sleep and successful students – explained
The list of sleep benefits seems to be never-ending. For young learners it’s important because:
- It improves learning and memory. During sleep, memories are consolidated – the important ones are strengthened and unimportant ones are “trimmed”, or forgotten. The brain also physically “washes out” wasteful chemicals from the brain and after this rejuvenation, our minds are well prepared for new learning.
- It speeds up thought processes and reactions. Sleeping well also means your teen will drive or bike more safely to school, making quick and smart decisions along the way. They are also more articulate in giving answers and thus more likely to participate in classroom activities.
- Sleep lowers stress and regulates mood. When stress and emotion brain centers are not overworked, teens are more likely to react reasonably and not get overwhelmed with emotions. Prolonged sleep deprivation almost always leads to depression and loneliness. Those who sleep poorly are also more likely to participate in bullying – both as bullies and victims.
- Sleep improves immunity and physical capabilities. When we sleep well our body is more prepared to fight diseases and it heals faster. Short sleep leads to hormonal imbalances and just a week of short six-hour sleep can “hormonally age” a young man through a testosterone reduction. Female hormones also suffer changes. When we count in poorer cognition, reaction and lost muscle mass due to poor sleep, we can’t expect our kids to be great athletes, regardless of how much training they do.
Poor sleep is found to be the third largest factor negatively affecting college student’s performance, just after stress and anxiety. So to prepare your teen adequately for college and future success, you need to help them understand the importance and establish a sensible study/life schedule and good sleep practices. Sleep and work/school productivity typically go hand-in-hand.
Technology plays a role
If you’re a parent, chances are you’re worried about your teen spending too much time in front of a computer, or staring at the TV or a smartphone. These devices, along with any other LED light sources, signal the brain to stay awake. Sleep doesn’t come easily if we look at screens right up until bedtime. To make matters worse, that sleep will be of poorer quality because the blue light inhibits melatonin which helps us fall asleep and stay asleep.
Social media also affects sleep, but unlike the blue light which physically sends signals to the brain, social media gives us a dopamine boost (this feel-good chemical which also keeps us awake). Another factor is the emotional response. Social media increases self-awareness, anxiety, and stress.
Teens and adults in general who check their phones just before bed have more chances of having sleep disturbances. This correlation between social media and sleep disturbances was found even in those who spend a lot of time on SNS throughout the day, not only night.
- Sleepmore in Seattle: Later school start times are associated with more sleep and better performance in high school students. https://advances.sciencemag.org/content/4/12/eaau6200
- Backgrounder: Later School Start Times. https://www.sleepfoundation.org/articles/backgrounder-later-school-start-times