Chronotypes change throughout lifetimes, especially during childhood and adolescence. Teens’ internal clocks run on different bio time than most adults’ clocks do. Teens are almost always, Wolves, the late chronotype that prefers afternoon and evening activity to mornings.

During adolescence, teens experience a biological shift to a later sleep-wake cycle. For teens, melatonin release occurs later in the evening—usually around 11 p.m.—and drops later in the morning. This biological shift to a Wolf chronotype explains why your teenager is full of energy and enthusiasm later in the day and evening, but can barely mumble a greeting or match his own socks first thing in the morning.

Teens’ Wolf-like bio time—also known as delayed sleep syndrome—puts teens at odds with typical schedules, especially with their early morning school start times. In recent years, there’s been some movement to change this disconnect between teenagers’ natural biological schedule and their school schedule. Schools around the country have begun to consider adopting later school start times.

A growing body of research indicates the benefits of later school times for teenagers. Studies have found that when teens start school later:

• Sleep amounts rise significantly. Teens don’t stay up later at night when their school start times change.
• Teens get better grades
• Fewer students seek help from counsellors and nurses
• Sick days and tardiness decrease
• Parents report their teenagers are easier to live with and more connected in their relationships at home
• Car accidents among teen drivers drop significantly

What parents can do:

Educate yourself about sleep. The National Sleep Foundation publishes a Sleep for Teens toolkit that lays out issues related to teen sleep and school start times. One of the most important ways you can help your teen sleep better is to understand yourself why sleep is so important.

Share what you learn. Talk to your teen’s school administration, to teachers and parents, and to the local community about the importance of sleep and the special sleep needs of teenagers. Advocate for sleep education in schools, for both educators and students.

Teens need between 8-10 hours of nightly sleep to meet their needs and to perform at their best during waking days. Because their bodies are biologically programmed to stay up late, it can be difficult for teens to get this much rest on a routine basis. The National Sleep Foundation estimates that only about 85 percent of teenagers are sleeping less than 8 ½ hours a night.

It is common for children to develop inconsistent sleep schedules during adolescence. Up late at night and up early during the school week, many teens sleep late on weekends, as a way to recover from the sleep debt they’ve accrued. But sleeping late on weekends only reinforces and enhances the delay in their bio clock, and makes it more difficult for them to fall asleep at a reasonable hour during the week. This erratic sleep schedule puts teens in a vicious cycle, in which they spend the week coping with a growing sleep debt, struggling to stay alert during the day, growing more and more tired as the week goes along. By the weekend they’re exhausted and ready to sleep in and the cycle begins all over again.

What parents can do:

Work with your teen to help them stay on a consistent schedule throughout the week and weekend. Set a bedtime and wake time that allows them to get the nightly sleep they need. (Every teen will be different, so pay attention to signs of sleep deprivation and adjust their targeted sleep amount accordingly.) On the weekends, it’s okay to let teens sleep in a little bit. An extra 30 minutes or an hour won’t throw off their bio clocks, and won’t leave them wide awake at midnight on Sunday evening. But keep the weekend sleep-ins to no more than 60 minutes of additional rest.

For teenagers, sleep is nothing less than fuel that powers their brain and its development. Sleep is a biological necessity and essential for health and daily functioning. It’s as important as a healthy diet and regular physical activity. At all stages of life, the brain is active during sleep consolidating memories and processing emotions, refreshing cells and clearing out build-up of waste materials that can slow or damage brain function. (There’s still a lot we don’t know yet about what’s happening in the brain during sleep, and why.)

In adolescence, the brain is still developing, and sleep is essential to healthy brain development. The brain’s pre-frontal cortex, responsible for complex thinking and decision making, as well as emotional regulation, is among the last areas of the brain to develop, and undergoes significant maturation during teenage years. This part of the brain is especially sensitive to the effects of sleep deprivation.

Short on sleep teens are at risk for a wide range of intellectual, social, emotional and behavioural problems. Insufficient sleep in teens is linked to:

What parents can do:

Prioritise sleep over late-night studying. Parents might think it’s worth it to allow teens to sacrifice some sleep for the sake of studying for a test. But research shows that teens who burn the midnight oil with homework are more likely to have trouble with their academic work the next day, including performing worse on tests and quizzes. Help your teen carve out time for homework so that it doesn’t compete with her regular bedtime.

Teach your teen the importance of sleep. Teens are interested in how things work in the world and why issues and choices matter. Spend some time educating your child about sleep and what it does for their minds and bodies and why it is so important to their health and their success. They’re likely to be more amenable to the sleep rules you lay out if they understand why the rules exist.

There are serious safety risks for teens who don’t get enough sleep. Insufficient sleep in teenagers raises their risks for sports injuries and other accidental injuries. One especially significant safety risk faced by sleep-deprived teens? Drowsy driving.

New and inexperienced drivers and sleepiness behind the wheel are a dangerous combination. According to research, teens are more than twice as likely to be involved in car accidents if they have slept poorly or felt sleepy while driving. More than half of sleep-related driving accidents involve drivers who are 25 years or younger. And nearly one-quarter of young adults report driving faster when they are tired and drowsy.

Drowsy driving is very similar to drunk driving. Research shows that being even a few hours short on sleep, sleeping only 4-5 hours a night, may make drivers as impaired behind the wheel as driving drunk.

When teens don’t get their recommended 8-10 hours of sleep a night on a regular basis, they are much more likely to be compromised behind the wheel, putting themselves and others at risk.

What parents can do:

Make driving rested as important as driving sober. You have a zero-tolerance policy you’re your teens about driving under the influence, right? Establish the same policy for drowsy driving.

Teach your teens to recognise the signs of drowsy driving, including:

• Repeated yawning and blinking
• Drifting outside of their lane
• Trouble remembering the miles they’ve just driven
• Hitting the curb at the edge of the road

Be a sleep-safety role model. Don’t drive drowsy yourself. By prioritising sleep and knowing when it isn’t safe for you to drive, you’re modelling strong sleep behaviours and good judgment for your teens.

You don’t need me to tell you that teenagers today are immersed in technology. Social media and digital devices are constant presences in most teens’ daily lives. Used without limits or awareness, technology can undermine sleep for teens.

More than 90 percent of teenagers use some form of digital technology in the hour before bedtime. Exposure to light from digital devices can delay the release of melatonin and push back sleep. This is especially problematic for teens who are already biologically pre-disposed to late sleep onset. Mental stimulation can keep teens’ minds active and alert at bedtime, which also may interfere with both sleep quantity and sleep quality. Research indicates that more highly interactive forms of technology – video games, cell phones, laptops and tablets—are more likely to interfere with sleep and lead to unrefreshing sleep.

The use of technology in the evenings is a major factor that can threaten teens’ sleep. But overall technology habits may also play a role. There is emerging evidence that heavy social media use by young adults is linked to sleep problems as well as greater risk for depression.

What parents can do:

Make bedrooms tech free. Your teen may resist, but the easiest and most effective way to stop technology from interfering with your teens’ sleep is to leave the cell phones and screens out of the bedroom. No nighttime light to interfere with your teen’s natural drowsiness, no middle of the night news alerts or texts buzzing on the phone at their bedside. Set up a central charging station somewhere in the house, and have your teens leave their phones and laptops there for the night. Set a digital cut off time for your household, a last-call for tweeting and Instagramming.

Pay attention to your teens’ social media and tech habits. Monitor not only your child’s interactions on social media, but their level of activity. Heavy use of social media and digital technology (the Internet, video games) may hurt your teen’s sleep, evening if they’re powering down at an appropriate time before bed.

Other tips for helping your teen sleep better:

Keep bedrooms cool. In addition to being dark and tech-free, a cool bedroom can help teens fall asleep more easily. In the evening, body temperature drops in preparation for sleep. A cool room enhances that internal temperature drop, and can help teens feel more sleepy, earlier. A warm bath or shower 90 minutes before bedtime can also help.

Do not exercise within 4 hours of bedtime. Exercise raises core body temperature, which can keep teens alert and interfere with their ability to wind down for sleep. That nighttime indoor soccer match that doesn’t finish until 9 p.m. may result in bedtime being pushed back, and a tired teen the next day. Have your teen wrap up all vigorous physical activity 4 hours before their scheduled lights out.

As parents, you can help your teenagers establish habits and attitudes about sleep that they will carry with them throughout their lifetimes.