Transparency Disclosure — We may receive a referral fee for products purchased through the links on our site…Read More.

School Start Time and Sleep: How Early Mornings Impact Students

Disclaimer – Nothing on this website is intended to be a substitute for professional medical advice, diagnosis, or treatment… Read More Here.

Whether you have children yourself or remember your own childhood, it’s no secret that getting kids up early for school isn’t always the easiest feat.

Early school start times can lead to less sleep for kids, or even a generally crabby child who just doesn’t want to get up so early to get ready to leave. High schoolers in particular, who tend to have the earliest school start times but often stay up later, face additional challenges with school and sleep.

Yet besides the frustration of simply waking kids up early, how does school start time affect sleep for our youngest population? Here’s what research and experts have to say.

Why Do Schools Start So Early?

The modern school system1 began in the late 19th century as school reformers fought for a more standardized school calendar in both urban and rural areas.  Before the reform, children went to the same schoolhouse at the same time every day, regardless of their age, with learning often starting around 9:00 a.m.

Then as automobiles and school buses made their way across America, the school system required an additional shift to accommodate busing runs2. This meant staggering school start times for elementary, middle, and high school students, who now learned separately, to ensure an efficient bus schedule.

These staggered start times also helped lessen traffic congestion and gave parents and caregivers time to drop children off at different schools.2

Average School Start Times Nationwide

While the average school start time3 varies slightly by state and age group (such as elementary, middle, or high school students), most schools start between 7:30 a.m. and 8:30 a.m.

According to the National Center for Education Statistics, the average start time for public high schools was 8:00 a.m. during the 2017 to 2018 school year, with 40 percent of these schools starting between 8:00 a.m. and 8:29 a.m.3

States with the earliest high school start times that school year included Nevada, Michigan, Pennsylvania, and West Virginia, all of which started before 8:00 a.m. Schools with the latest high school start times included Iowa, Minnesota, and South Carolina, the latter of which averages 8:34 a.m.

Importance of Sleep for Kids and Teenagers

Sleep does more than make us feel well-rested. As an integral part of our health, sleep is especially important for growing kids and teens, since the human growth hormone4  is released during sleep. Sleep5 also promotes learning, memory formation, emotional regulation, and physical and mental development for kids and adults alike.

While you may have heard that infants need up to 17 hours of sleep per day, even 18-year-olds, many of whom are seniors in high school, still require at least eight to 10 hours of sleep6 per night to function at their best.

When we don’t get enough sleep, the human growth hormone is suppressed, which could potentially stunt growth if sleep loss becomes chronic.4 That’s why many people advocate for later school start times, especially for teens who tend to stay up later and have some of the earliest school start times.

Learn more: Teens and Sleep

Benefits of a Shifted Schedule for School Start Times

Numerous physical and mental health benefits point in favor of a shifted schedule for school start times to begin and end later in the day. These are a few potential pros of starting school at a later time.

More Sleep

Arguably the biggest benefit of a shifted schedule for school start times is more sleep for all, including both parents and kids. Teens, in particular, may benefit from later start times, explains pediatrician Leah Alexander, MD.

“The increase of estrogen, testosterone, and other androgens have direct effects on the brain during puberty,” she explains of the shifting circadian rhythm in teens. “As a result, preteens and teens experience a change in their sleep patterns, often with later bedtimes and longer morning sleep.” – Pediatrician Leah Alexander, MD.

Reduced Risk of Accidents

Another benefit of a shifted school schedule for the teenage population is the potential for a reduced risk of accidents for teens who drive to school.

“‘Drowsy driving’ can impair responsiveness in both teens and adults,” Alexander says. “Most of the accidents7 that occur while sleep-deprived are between 6:00 a.m. and noon.”

Improved Behavior and Mood

Sleep is critical for supporting the rapidly developing brains of kids and teens. However, insufficient sleep8 in this age group can lead to impulsivity, stress, depression, anxiety, aggressive behavior, and thinking problems, all of which can affect a child’s experience at school and with other classmates. Therefore, getting enough sleep is critical for mood and well-being.

Better Performance in School

Still, it’s not just behavior that’s affected by sleep.

Research shows that kids who don’t get enough sleep may struggle with decision-making, conflict-solving, and working memory; this is because sleep causes specific brain changes that affect the way we learn.8

Combined, these factors can negatively impact school performance, further supporting the argument for shifted schedules for school start times.

Find Out More: Importance of Sleep for Students’ Success

Learn More: Best Mattress for Kids and Best Mattress for Teenagers

Downsides of Later School Start Times

While starting school at a later time comes with a plethora of health and wellness benefits, there are also a few potential downsides to this scenario. Here’s why some people argue against later school start times.

Interference with Extracurricular Activities 

Many kids are enrolled in extracurricular activities like after-school sports, while older teens may have jobs they go to after school. Starting school later would inevitably push school end time, potentially interfering with other responsibilities.

Related: Athletes and Sleep

Could Impact Transportation Options

The main reason elementary, middle, and high school start times were staggered in the first place was to accommodate busing runs, lessen road congestion, and give parents enough time to drop off kids at different schools.2 Later school start times could potentially disrupt all three. 

Late-Night Homework

Let’s say your child arrives home from school around 3:00 p.m. This gives your kid at least two-to-three solid hours of time to complete their homework before dinner, leaving them plenty of time to unwind and relax before bed.

By shifting school start times forward, kids may have less time for homework directly after school, forcing them to complete their homework later at night (and potentially sleep even less than with earlier school start times).

Could Impact Teacher and Family Schedules

Kids and teens aren’t the only ones who would be impacted by shifted school start times. A later start time would require later working hours for teachers, which could impact their family time or life outside of work.

The same rings true for family schedules, especially families with kids enrolled in extracurricular activities or for parents reliant on their work schedules to be able to drop off and pick up their kids from school.

Tips to Help Kids Cope with Early School Start Times

Choose the Right Bedtime

If you aren’t sure what bedtime is appropriate, consult the chart below to determine the total hours of sleep your child needs, then count back from when they must wake up to be on time for school.

AgeHours of Sleep Needed Each Day
Children (3 to 5 years)10 – 13 hours 
Children (6 to 12 years)9 – 12 hours
Teenagers (13 to 18 years)8 – 10 hours

Source: American Academy of Sleep Medicine

Minimize Electronics Before Bed

You may have heard by now that you should avoid screen time before bed, but the reasoning goes beyond simply taking a break from your smartphone.

Blue light9 emitted by cellphones, tablets, and computers interferes with melatonin production, an important hormone for promoting sleep. With kids and teens ever reliant on phones and iPads for communication and entertainment, it’s a good idea to promote healthy sleep habits in your home like putting away or steering clear of electronics before bed.

“I typically recommend turning these devices off 30-to-60 minutes prior to trying to fall asleep,”- Pediatrician Leah Alexander, MD.

Get More Info: How Technology Impacts Your Sleep

Improve their Quality of Sleep

Parents and caregivers can help kids and teens get better and more sleep by taking a few simple steps to optimize their sleep environment. Bedrooms should be cool, dark, and quiet, so you might consider investing in blackout shades or a floor fan to help promote the ideal sleep space.

Read More: Benefits of Sleeping in a Cold Room

Investing in a good mattress and bedding can also pay itself off by helping your children get better rest. An old mattress, for example, might sag, have springs sticking out, or cause discomfort, which could keep kids awake.

During summer months, opt for cool cotton bedding, while those who live in areas with colder winters can also use flannel bedding to stay warm during chilly months.

Lastly, be sure to address any underlying concerns that might interfere with your child’s sleep, such as a potential sleep disorder or behavioral reason for trouble sleeping.

Avoid Caffeine and Sugar

Kids love sugar, while teens may crave caffeine and energy drinks. Although caffeine and sugar won’t hurt on occasion, you’ll want to consider limiting your kids’ consumption before bedtime, as both can interfere with sleep by making them more alert.

Maintain a Bedtime Routine

There’s no one bedtime routine that works the same for all, but some options to consider adding to a nightly routine include taking a warm bath or reading a book before bed, both of which can help kids and teens relax.

“Good sleep hygiene and a consistent bedtime routine is the ideal way to ensure kids and teens get enough sleep,” – Pediatrician Leah Alexander, MD.

School Start Time FAQs 

Why do schools start so early in August?

Starting school early in August10 boils down to one simple principle: to improve student attendance in the spring with an earlier end to the school year.

Why do Texas schools start so early?

Texas schools11 are pushing for earlier start dates to help create two academic semesters of equal length, which school officials argue allows them more time to prepare for state assessment tests.

Why do high schools start so early?

High schools start early to accommodate school busing schedules, which allows buses to have enough time to make additional runs for middle school and elementary school students.2

Ashley Zlatopolsky

Ashley Zlatopolsky

Content Writer

About Author

Ashley Zlatopolsky is a Detroit-based writer and editor who specializes in sleep content. She writes about sleep health, hygiene and products for Sleep Advisor, Mattress Clarity, Real Simple, and more.

Side Sleeper


  1. De Melker, Saskia and Weber, Sam. “Agrarian roots? Think again. Debunking the myth of summer vacation’s origins”. PBS News. 2014.
  2. Bastian, Kevin., Crittenden Fuller, Sarah. “What new research tells us about elementary and middle school start times”. Brookings. 2023.
  3. “Average start time a.m.”. National Center for Education Statistics. 2020.
  4. “Can lack of sleep stunt your growth?” Nemours Teen Health. 2021.
  5. Gehrman, Elizabeth. “A child’s need for sleep”. Harvard Medicine.
  6. “Teen Sleep Duration Health Advisory”. American Academy of Sleep Medicine. Last modified April 3, 2016.
  7. “Drowsy driving”. National Highway Traffic Safety Administration. Webpage accessed April 26, 2024.
  8. Contie, Vicki. “Children’s sleep linked to brain development”. National Institutes of Health. 2022.
  9. “Blue light has a dark side”. Harvard Health Publishing. 2020.
  10. Slagter, Martin. “It’s Michigan law to start school after Labor Day. So why are most starting earlier?” MLive. 2022.
  11. Smith, Corbett. “Is your kids’ school starting earlier and earlier? Yes, and here’s why”. The Dallas Morning News. 2019.