Over the past year or two, there have been more conversations about school start times. Specifically, there has been more discussion about high school start times being too early. The topic is popping up in newspaper editorials, educational conferences and even backyard summer conversations.

Why are people talking about this now? The majority of school districts in the United States begin their school day before 8:30 a.m.; has something changed to make us think that this is no longer acceptable?

To answer the second question first, the major change over the past decade is that we have gained a better understanding and awareness of two basic scientific concepts: the importance of sleep and the natural shift in circadian rhythms in adolescence.

Societal value on sleep has shifted over the years, but recently, there’s been an abundance of evidence to support the age-old wisdom that sleep is important. Lack of sleep has a direct effect on multiple short- and long-term outcomes.

Short-term negative outcomes from lack of sleep include poorer academic performance, poorer athletic performance, riskier/impulsive behaviors and increased automobile accidents. Long-term negative outcomes from lack of sleep include obesity, heart disease and growth suppression. Luckily, the opposite is true and getting sufficient sleep helps to reduce all of the above-mentioned short- and long-term consequences. How much sleep is needed? The Centers for Disease Control and Prevention (CDC) recommends 8 to 10 hours of sleep for adolescents and most sleep experts believe that 8.5-9 hours seems to be the correct amount. Eight hours seems to be a critical point for preventing much of the negative outcomes mentioned above.

Adolescence Circadian Rhythm The concept of circadian rhythm changes in adolescence is not new to anyone; in fact, almost all adults have experienced this during adolescence and should be able to relate. We know that during the teen years, melatonin, a hormone released by the pineal gland in the brain to help initiate sleep, has its release shifted two to three hours later than it was in childhood. The result of this shift in melatonin release means that teens who previously had been able to fall asleep between 8 p.m. and 9 p.m. now cannot fall asleep until 10:30 p.m. to 11 p.m. It also means that these teens have a hard time waking up before 7 a.m., since the melatonin release often continues in teens through sunrise. This shift in melatonin release has been documented to occur worldwide and is not a new phenomenon. Once teens become young adults in their early to mid-20s, the melatonin release often shifts back to follow a more typical adult sleep schedule.

Taken together, these two facts have changed much of our thinking about adolescence, sleep and school start times. If we know adolescents need a minimum of eight hours of sleep to prevent the consequences listed above and we know that they cannot fall asleep until 10:30 to 11 p.m., then we know we shouldn’t wake them up until 6:30 to 7 a.m. at the earliest. Working from there, we know that we should be giving them time to get up, eat breakfast, get ready for school and then time to commute to school, usually on the school bus. Those calculations result in the general recommendations for starting school for middle and high schoolers no earlier than 8:30 a.m.

In 2014, the American Academy of Pediatrics published its policy statement, entitled “School Start Times for Adolescence,” in which the authors expertly reviewed the data surrounding sleep and changes in adolescent circadian rhythms, and recommended that middle and high school start times not begin before 8:30 a.m. The CDC, the American Academy of Sleep Medicine, and many other national health organizations have also made the same recommendations.

Educators have long recognized that in districts where high school starts early, many of the students are either late for school or are not paying attention during the first and second periods of the day. Parents have long recognized that their adolescents seem exhausted and are difficult to wake up in the morning, resulting in them rushing their teens to school. So how did we get here and why haven’t we changed anything?

Why Do High Schools Start Earlier? First, it’s important to recognize that the science mentioned above is evidence- based and there are no real opposing viewpoints. There has not been any rationale that adolescents receive better education when they start schools early and it has not always been this way. The big push to move high schools to an earlier start time began in the 1970s and 1980s. As towns grew, schools became larger and transportation needs increased. As a cost-savings technique, towns turned to tiered busing systems, using fewer buses and bus drivers and having them repeat multiple loops with staggered start times. By convention, high schools often were shifted earlier and that process continues through the present day. Today, many towns have three staggered start times and often begin the high school students earliest and the younger elementary school students latest.

Though there is no benefit to starting school earlier for high school students, there has been a benefit to ending school earlier. Athletics typically benefits from earlier school end times, by allowing more time for practice and transportation to away games. Other benefits of ending school times earlier for adolescents include allowing more time to get to after-school jobs, helping with child care for younger siblings and allowing use of the school by other community organizations.

Now to answer the first question: Why are people talking about this now? As we have become more aware of the importance of sleep and the changes in adolescent circadian rhythms, school administrators and boards of education have begun to re-think school policies to see if they can help solve these problems. Keeping student health, education and well-being as the driving principle, they have found solutions to the three common problems that most districts face when considering the issue of school start times: transportation, athletic schedules and resistance to change.

The Obstacles Small towns and big cities have both been successful in finding ways to make this change. In many towns, transportation has been the first hurdle. Schools have been successful in solving the transportation dilemma in multiple ways, including swapping schedules and having the younger children start school first and the older ones later, tightening bus routes or reducing tiers and finding the money to offset the increase in transportation costs.

Athletics, a priority for many parents and educators and often a seemingly huge hurdle, has been successfully managed by school districts as well. Rotating bell schedules, implementing Option 2 programs allowing high school sports to count in place of gym, eliminating waste from the schedule and creating as early a school end as possible have been some of the solutions. Athletic directors have also looked to create efficiencies in practices, limiting them to 90 minutes, game transportation and to create more serial game play with freshman, junior varsity and varsity teams playing at the same time on separate fields.

Last, changing school start schedules, which families, teachers and the community base their home life schedule around, is often difficult. Successful districts have accomplished this change though open communication, explaining the rationale, inviting input and allowing time to adjust people’s schedules.

More and more schools are successfully implementing this and leading this way for other schools. Data from these schools after they have changed start times support the success of the program and help to dispel many of the myths that people mention when discussing the difficulty of changing school start times. The data supports that when you delay school start times, bedtimes do not change and that students gain an average of almost a minute of sleep for every minute of delayed school start times. Tardiness, absences and automobile accidents decrease and academic performance increases. Best of all, parents report that their teens are in better moods and are more pleasant to be around.

Legislators have been weighing in too. California recently approved legislation that mandates school start times for high schools begin at 8:30 a.m. or later. New Jersey recently passed legislation to pilot a four-year study of later school start times in five districts. Things are starting to move in the right direction.

A Board’s Priority What should a school board do now? The evidence is clear — if our job is to create the most successful environment for an adolescent to learn, grow and prosper, we should be finding ways to allow them to sleep more and not start school earlier than necessary.

Ideally, this would be legislated at a state or federal level, compelling all schools to be consistent with these recommendations for school start times. However, legislation is difficult. In 2018, both the California state Assembly and state Senate passed legislation for later school start times, only to have it vetoed by the governor. The rationale for the veto, although all the lawmakers supported the concept of delayed school start times, was that they thought the decision should be a local one.

So the decision is in the hands of the board of education. There is clear evidence that a change in policy regarding school start times can have a direct and immediate positive impact on the adolescents in the district. The obstacles to making the change are known, but surmountable. This is a problem where science and common sense are on the same side and in most cases, bright committed adults can come together as a community to find solutions and create a healthier and better learning environment for our teens. And after all, isn’t that the priority of all of us?

Dr. Bert Mandelbaum is a pediatrician with Princeton Nassau Pediatrics; the chairman of the department of pediatrics at Penn Medicine Princeton Health Center; and school physician for the Montgomery Township school district.