B. Sleep Scientists on the Timing of Education

“The timing of education is also important. There is clear evidence for a phase shift during adolescence, with adolescents going to bed later and rising later than children. This phase shift is largely biological, with adolescents typically unable to fall asleep at earlier times. For the most part, school systems have not considered this adolescent phase shift, with many systems traditionally having earlier (rather than later) start dates for high school than for grade school students. By recognizing the shift in biological rhythms during adolescence and delaying school start times accordingly, classroom experience can be matched to the times when adolescents are most alert and attentive.”—Donna Coch, Ed.D., Associate Professor and Chair, Department of Education, Dartmouth College, Kurt Fischer, Ph.D., Charles Bigelow Professor of Education, Director, Mind, Brain, and Education Program, Harvard University, Geraldine Dawson, Ph.D., Professor of Psychiatry and Behavioral Sciences, Duke University Medical Center. (CochFischer, & Dawson, Human Behavior, Learning, and the Developing Brain: Typical Development (Informa Healthcare 2010) pp. 382-383.)

“There is a need for educators to be more aware of the impact of school start times and academic scheduling, and to consider sleep problems as potential factors in students who fail to achieve or who exhibit behavioural problems. While it may be administratively convenient to begin high school classes early, there is strong evidence in our data, supported by the literature, suggesting that later start times would be more appropriate for teens.” (63)

“Students at later starting middle and high schools obtain more sleep due to later wake times and, in turn, function more effectively in school.” (30) 

“Where possible, efforts should be made to encourage lighter homework loads and later school start times, so that adolescents can go to bed and wake up at times that are more suited to their bodily rhythms.” (23)

“[S]chools need to incorporate into their pedagogical proposal measures that would reduce the impact of phase delay on the student’s performance. [¶] The first step would be to reconsider the school’s temporal organization, in particular its class schedules, and systematize the results of possible interventions that aim to reduce the student’s daily sleepiness and thereby improve performance. [¶] The changes we propose are apparently simple modifications, such as delaying the beginning of morning classes.” (575

“For policy makers, teachers and parents, these results provide a clear mandate. The effects of sleep deprivation on grades, car accident risk, and mood are indisputable. A number of school districts have moved middle and high school start times later with the goal of decreasing teenage sleep deprivation. We support this approach, as results indicate that later school start times lead to decreased truancy and drop-out rates.” (103)

“Recent research has focused on the effects of daytime sleepiness in the student population. Poor sleep quality has been linked to increased tension, irritability, depression, more frequent use of alcohol and illicit drugs, accidents, and lowered academic performance. Sleep problems are common and unrecognized in the student group. The influence of sleep on learning and behavior has recently captured the attention of school districts across the United States and school administrators increasingly need to weigh the factual information about the biology of student sleep patterns against the competing demands of teachers’ work preferences and athletic and after-school schedules. [¶] [T]here is increasing data that early school start times result in increased daytime sleepiness, and altering the times to a later time period has positive effects on academic performance and sleepiness.” (Bijwadia & Dexter, The Student with Sleep Complaints, publish. in, Sleep: A Comprehensive Handbook (Lee-Chiong, edit., Wiley-Liss 2006) pp. 959, 960.)

“School administrators would serve students and teachers better by moving the opening bell later. The weight of the evidence from decades of studies suggests that creating conditions to encourage student sleep would improve the students’ mood, energy, alertness, and academic performance. [¶] Schools are not solely responsible for the perfect storm of teen sleep, but they can make a huge difference by moving to a later start time. The result would be happier, healthier, more attentive, and better performing students in high school.” (610)

“[C]hildren and adolescents with restricted sleep are at greater risk for increased oppositionality and irritability, as well as reduced attention, executive functioning, processing speed, behavioral/emotional regulation, motivation and academic achievement. … Certainly this causal link between sleep loss and impaired functioning in children and adolescents provides the impetus for consideration of delaying school start times, particularly for adolescents, who are experiencing a natural delay in circadian rhythm.” (611)

Start Time Recommendations, etc.

“The often serious impact of this chronic under-sleeping is now evident in both high school and middle school students. [¶] For all students one of the most salient—and correctable—social factors contributing to student sleep deprivation, is school start times. [¶] In brief, there are two features of the circadian rhythm especially important to understand regarding sleep in teenagers: (1) the drowsy signal that cues bedtime is dependent on the dampening of circadian-dependent alertness; and (2) the physiology of puberty causes a shift in the circadian rhythm which delays the timing of this biological bedtime by about an hour. These two biological factors underlie the main difficulties faced by adolescents attending school before 9:00 a.m.: the general problem that one cannot easily fall asleep before their biological bedtime, and the additional problem that puberty creates a tendency for even later bedtimes. [¶] Though research has not yet identified an ideal school schedule, the wealth of evidence reviewed in this chapter and elsewhere strongly suggests that students have a better opportunity to be rested and ready to learn by delaying school start time to 8:30 a.m. or later.” (2)

“[G]iven the analyses summarized here, there are clear benefits for students whose high schools start at 8:30 AM or later. This would include, for teens who reported they got at least 8 hours of sleep per night, that they were more likely to say they have good overall health and were less likely to report being depressed or using caffeine and other substances (e.g., alcohol, tobacco, other drugs). Other positive findings include a significant reduction in local car crashes, less absenteeism, less tardiness, as well as higher test scores on national achievement tests. … [¶] … [T]here are empirically-based positive outcomes for adolescents whenever the start time of their high school is moved to a later time—with the starting time of 8:30 AM or later clearly showing the most positive results.” (309)

“During the school year, many teenagers find themselves nodding off during their early morning classes as high school bells ring around 7:30 a.m. While parents and teachers may attribute falling asleep during class to staying up too late checking Facebook statuses and texting with friends, medical evidence suggests that an early school start time before 8:30 a.m. is a greater culprit because classes are occurring when students’ brains and bodies are still in biological sleep mode.” (341)

“There are at least three policy changes that will assist in the prioritization of sleep: 1) healthcare policy requiring the inclusion of sleep questions on health service intake forms and health provider prompts, in much the same way that smoking or exercise are routinely discussed; 2) education policy mandating school start times no earlier than 9 a.m. for adolescents; and 3) medical education policy limiting the hours of medical interns’ and residents’ shifts.” (629)

“The study strongly recommends that middle schools should consider delaying the school starting time by at least one hour. Such a change could enhance students’ cognitive performance by improving their attention level, increasing rate of performance, as well as reducing their mistakes and impulsivity.” (13, italics added [study shifted school schedules from 7:30 a.m. to 8:30 a.m.].)

“Schools with start times before 8:30 a.m. place students at a disadvantage in terms of arousal and alertness, not only for early morning classes but also throughout the day because adolescents’ biological rhythms are out of sync with typical school routines.” (11)

“Right now, high schools usually start earlier in the morning than elementary schools. But if school start times were based on sleep cycles, elementary schools should start at 7:30 and high schools at 8:30 or 8:45—right now it’s the reverse. School systems should be thinking about changing their start times. It would not be easy—they would have to change the busing system—but it would increase their student’s sleep time and likely improve their school performance.” (542)

Coloradocapitolhill2“Although providing a home environment to promote healthy sleep is the first step to eliminating sleep deprivation in adolescents, increased public awareness of the impact of sleep on learning and behavior is important. For this to occur legislation to ensure that high school start times not begin before 9:00 a.m. may help in reducing sleep deprivation leading to improved academic performance and behavior[.]” (15)

“Another short-term solution that can be implemented is to change the time we give standardized tests to 10:00 a.m. Almost all standardized tests in high schools begin at 8 am. Because this is when adolescents show their poorest performance levels, a change is clearly needed and would be relatively easy to negotiate.” (6but see, n. 261 [study of 9th and 10th graders found “larks” outperformed “owls” on exams administered from 10 a.m. to noon].)

“Overall, many adolescents confront a major challenge if schools begin earlier than 8:30 a.m.; many schools start too early in the morning for adolescents to get adequate sleep, whether in the United States or in other countries such as Canada, Israel, Brazil, or Italy. [¶] [S]chool administrators are being urged to acknowledge the evidence and to adjust school schedules accordingly (e.g., delay high school start times).” (12, citations omitted.)

“High school should start at 8:45 a.m., or better at 9 o’clock.” (630) 

“A long-term solution to chronic sleep deprivation in adolescents that others conducting research on adolescent sleep behaviors support may mean that high school start times should be no earlier than 8:30 A.M. The change in high school start times will need to occur at the state level so that school sports and social events can be coordinated among schools.” (100)

“Probably, 9 o’clock would be the ideal start time for high schools.” (634)

“In 1913, Terman and Hocking (1913) reported that sleep in adolescents in the western U.S. was longer than that previously reported in studies of English (n=6180) (Ravenhill 1910) or German (Bernhard 1908) children and adolescents. One of the factors that they felt explained this difference was that school start times were an hour later (9:00 AM) in the U.S. than those in Germany and England (7:00–8:00 AM). They go so far as to state, ‘The American practice of beginning at 9 o’clock is far wiser, and should never be changed unless for very special reasons.’ ” (305quoting Terman & Hocking, The sleep of school children; its distribution according to age, and its relation to physical and mental efficiency (1913) J. Educational Psychology, p. 271.)

“[F]urther research now shows that in adolescence protecting our children’s health and improving their learning means school starting times later than 9 a.m.”  (612)

sleep scientists cartoon






The Appendix, infra, Start Time Recommendations, etc. (html, docx, pdf), includes the text above and additional recommendations from scientists and economists with full citations, author credentials, and links to author profiles (where available).


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