Your teen is wide awake at 11 p.m. and impossible to wake at 7 a.m. It isn't laziness. Biology, school start times and screens all play a part. Here's what helps.
Written by Vita Globe Editorial Team | Reviewed against AAP policy, AASM guidance and peer-reviewed research
Why do teenagers stay up so late?
During puberty, the body clock shifts later and sleep pressure builds more slowly, so teens naturally feel alert later at night[1]. Add early school start times and evening screens, and many fall short of the 8 to 10 hours recommended for ages 13 to 18[2]. The AAP has recommended middle and high schools start no earlier than 8:30 a.m.[3]
Caveat: Families can't change biology or school start times, but consistent wake times, morning light and fewer late-night screens can help.
Sources: Crowley 2018 · AASM (children) · AAP 2014 · Verified 2026-09-28
IN THIS ARTICLE
Is it true that teens' body clocks change?
Yes. Researchers describe a “perfect storm” in adolescence: the body clock shifts later, the drive to sleep builds more slowly during the day, and at the same time teens face more homework, activities, screens and early school start times[1]. The result is a teen who genuinely isn't sleepy at 9:30 p.m.
How much sleep does a teenager need?
The American Academy of Sleep Medicine recommends 8 to 10 hours per 24 hours for ages 13 to 18[2]. The American Academy of Pediatrics puts the typical need at about 8.5 to 9.5 hours and has called insufficient sleep in teens an important public health issue[3]. The AAP recommends middle and high schools start at 8:30 a.m. or later to help teens get enough sleep[3].
How much do phones affect teen sleep?
A lot, according to the research. A meta-analysis of 20 studies found that using a portable device at bedtime was linked with inadequate sleep, poorer sleep quality and more daytime sleepiness, and simply having one in the bedroom was linked with worse sleep[4]. Late-night phone use also means bright light when the body clock is already running late.
A phone-free bedroom is hard to sell to a teen, but it's one of the few levers parents have. Our post on setting a family screen curfew walks through how to set one up as a family.
What can parents actually do to help?
- Anchor the wake-up time. Keep weekend wake-ups within an hour or two of school days to limit the Monday crash.
- Morning light. Open blinds, eat breakfast by a window, walk part of the way to school.
- Dim evenings. Lower lights after dinner. Room light before bed delays melatonin[5].
- Phones charge outside the bedroom with a regular alarm clock instead.
- Limit late caffeine. Energy drinks and afternoon coffee make a late clock later. See our post on caffeine and family sleep.
- Talk, don't lecture. Teens respond better to understanding why sleep affects mood, sports and grades.
The honest summary
- Teen body clocks really do shift later. It's biology, not just attitude.
- Teens need about 8 to 10 hours, and many get far less on school nights.
- Screens in the bedroom are one of the most consistent sleep disruptors.
- Consistent wake times, morning light and dim evenings help the most at home.
Should teens take melatonin?
Talk to your teen's doctor first. Pediatric sleep experts recommend trying schedule and behavior changes before melatonin and, if it's used, getting guidance on dose and timing[6]. Melatonin is a timing signal, not a sedative, so it won't make up for a phone in bed at midnight. If your teen has ongoing trouble falling asleep, a pediatrician can check for other causes. For more, see whether kids can take melatonin every night.
Our option
Vita Globe Happy Sleep Bundle
For households where younger kids and adults have occasional sleepless nights, the Happy Sleep Bundle covers both in one box. It pairs our Melatonin 5mg Gummies for adults (5mg per serving) with Kids' Melatonin 1mg Gummies (1mg per gummy), so each person uses the formula dosed for their age group. Both are non-GMO and gluten-free, tested by an independent third-party lab, and intended for occasional sleeplessness. Check with your pediatrician before giving melatonin to a child.
Frequently asked questions
What time should a 15-year-old go to bed?
Count back 8 to 10 hours from wake-up time[2]. With a 6:30 a.m. alarm, that's roughly 8:30 to 10:30 p.m., though many teens find the earlier end hard because of their later body clock.
Is it normal for teenagers to sleep until noon on weekends?
It's common, and usually a sign of weekday sleep debt plus a later body clock. It can make Monday mornings harder, so try to keep weekend wake-ups closer to school days.
Why is my teen tired all the time?
Short school-night sleep is one of the most common reasons. If your teen gets enough sleep and is still exhausted, snores loudly or seems low in mood, talk to their doctor.
Do later school start times really help?
The AAP recommends start times of 8:30 a.m. or later for middle and high schools, citing benefits for sleep and well-being[3].
Sources
- Crowley SJ, Wolfson AR, Tarokh L, Carskadon MA. An update on adolescent sleep: new evidence informing the perfect storm model. J Adolesc. 2018;67:55-65. doi:10.1016/j.adolescence.2018.06.001
- Paruthi S, Brooks LJ, D'Ambrosio C, et al. Recommended amount of sleep for pediatric populations: a consensus statement of the American Academy of Sleep Medicine. J Clin Sleep Med. 2016;12(6):785-786. doi:10.5664/jcsm.5866
- Adolescent Sleep Working Group; Committee on Adolescence; Council on School Health. School start times for adolescents. Pediatrics. 2014;134(3):642-649. doi:10.1542/peds.2014-1697
- Carter B, Rees P, Hale L, Bhattacharjee D, Paradkar MS. Association between portable screen-based media device access or use and sleep outcomes: a systematic review and meta-analysis. JAMA Pediatr. 2016;170(12):1202-1208. doi:10.1001/jamapediatrics.2016.2341
- Gooley JJ, Chamberlain K, Smith KA, et al. Exposure to room light before bedtime suppresses melatonin onset and shortens melatonin duration in humans. J Clin Endocrinol Metab. 2011;96(3):E463-E472. doi:10.1210/jc.2010-2098
- American Academy of Sleep Medicine. Health advisory: melatonin use in children and adolescents. 2022. aasm.org
About the Vita Globe Editorial Team
The Vita Globe Editorial Team researches and writes our wellness content, working from peer-reviewed research, systematic reviews and guidance from bodies such as the NIH and the FDA. We cite our sources inline and update articles when the evidence changes.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. This article is for informational purposes only and is not a substitute for medical advice. Talk to your healthcare provider before starting any new supplement, particularly if you are pregnant, nursing, taking medication, or caring for a child.
