Yawning and drowsiness are not the only signs that a student is getting too little sleep. Other symptoms put forward by research include hyperactivity, crankiness, impulsiveness, and a short attention span. Sleep loss also has less obvious effects on health, emotions, academic success, and driving ability. These effects have long-term consequences in the educational setting but also for healthy living and skill development outside school.

Sleep and school

Sleep has beneficial effects on our health, emotions, memory, and academic potential. Inadequate sleep, however, can negatively affect our well-being, decision-making, and attention, all of which are necessary for success in school. Elementary school and early high school have been identified as critical periods for affecting and establishing healthy habits in children. Because of sleep’s vital impact on the health and performance of students, it is important to emphasize good bedtime habits in our homes, communities, and especially in our schools during this time.

As a society, we are sleeping less and less. One in four Canadians is sleep-deprived and 60–70% of Canadian students are often very sleepy during their morning classes. School-aged children are experiencing delayed bedtimes and nearly half of Canadian teens reported at least occasional problems falling or staying asleep.

Night time difficulties have become common and are hindering the ability of students to thrive in school. Twenty to forty percent of young children are estimated to have sleep problems and of approximately two million Canadians between the ages of 14 and 18 years, as many as 975,000 suffer from a serious lack of sleep. On top of that, almost 13% of teenagers are experiencing severe insomnia. Lost sleep on weeknights combined with unhealthy bedtime habits on weekends are triggering difficulties that manifest during the school week.

Reducing sleep may disrupt the ability of students to concentrate for long periods of time, and remember what they learn in class. According to a study, children with reduced sleep are more likely to struggle with verbal creativity, problem solving, inhibiting their behaviour, and generally score lower on IQ tests according to current leading research.

The consequences on school performance are evident. Up to 24% of teenage students have reported that their grades dropped because of sleepiness. In addition, a study has shown that students who had grades of C, D, or E averaged 25 to 30 minutes less sleep per weeknight than their classmates who achieved A’s or B’s.

Sleep and sociocultural environment

The consequences of poor sleep may be long term. Just as nutrition and exercise must be included in healthy lifestyle choices, sleep habits must also be considered in this balance. This requires prioritizing our sleep needs within school, family, and community settings. When choosing how to balance our cultural and personal commitments with our sleep requirements, it is helpful to remember that sleep is an important factor for performing at our best physically, mentally, and emotionally. When we put off sleep to study or to practice a skill, we may actually be preventing our mind from absorbing the information we want it to retain or our bodies from developing as we had hoped.

Another factor to be considered with evening activities is how much they stimulate a child. Although physical activity during the day is healthy for sleep, our bodies need time to cool down after exercise. Similarly, our minds need time to settle down after activities that require deep concentration. In addition, the stress of performing well, whether it be in an organized activity or a social context, may keep us from falling asleep easily if it occurs too close to bedtime.


Homework may affect a child’s sleep in three ways. First, the time it takes to finish an assignment may infringe on time that should be used for sleeping. Second, work done too close to bedtime may leave a child too stimulated to fall asleep easily. Finally, if homework is done on or near a child’s bed, the child may associate that area with working or stress and not be able to fall asleep easily there.

Home entertainment and technology

Watching television, movies, or video games close to bedtime may all contribute to a loss of sleep. Although we may feel and appear calm when enjoying these types of entertainment, our minds are excited. If we don’t have enough downtime before going to bed, it may be difficult to fall asleep. Further, children engaging in content that is inappropriate for their age may make it difficult for them to sleep as they can get anxious or scared. Such content may increase the chance of nightmares during the night as well. Finally, using entertainment technology too close to bedtime may lead to using these devices after we should already be in bed.

Eating Habits

A heavy meal right before bedtime can make it difficult to sleep. On the other hand, going to bed on an empty stomach can do the same thing, so finding a balance is necessary.


Caffeine is a stimulant found in many items such as chocolate, chocolate milk, tea, iced tea, soft drinks, coffee, some herbal remedies, and many over-the-counter pain and cold medicines. Caffeine can help us function during the day, but it may also cause problems sleeping at night.

Tobacco and alcohol

Although consuming alcohol may make us fall asleep easier at first, it acts as a stimulant as it gets digested which may cause us to wake up throughout the night and intensify or create sleep disorders. Similarly, smoking may worsen many sleep disorders and can cause others such as restless leg syndrome and sleep disordered breathing.

Sleep and health

Several physiological functions are strongly affected by insufficient sleep:

  • The regulation of the neurohormones leptin and ghrelin
  • The control of glucose level, increasing children’s risk of diabetes
  • The control of cardiovascular function

These are key risk factors for the development of obesity.

It has been found that not getting enough sleep is related to the development of childhood obesity in Quebec. Children whose parents have weight problems have a much greater chance of developing weight problems themselves. This could be the result of genetics or of having learned poor eating habits from their parents. Like eating habits, sleep habits are closely related to a family’s lifestyle, and it has been shown that many children sleep less than they need. This is important because short sleep duration produces hormonal changes comparable to those associated with increased risks of obesity, diabetes, and hypertension.

Sleep and Driving

Many studies have shown that reduced sleep impairs a teenager’s driving ability. Car crashes are more frequent in young drivers that sleep less than 7 hours a night compared to those that get more. Other research concludes that teenagers are more at risk if they have poor sleep quality, daytime sleepiness, or drive late at night. This is a major issue with adolescents who are learning to drive, are regularly sleep-deprived, and are experimenting with alcohol.

This content was developped by Reut Gruber, PhD, thanks to the support of Manulife.

[Sleep and children: the science behind it] [Sleep disorders in children] [Sleep and children: the impact of lack of sleep on daily life] [Sleep and children: practical advice] [Sleep and youth : five common myths]