A movement to shift secondary school start times to after 8:30 a.m. is gaining momentum. This is based on multiple scientific studies showing that later start times improve student sleep, health, safety, and performance. We interviewed Terra Ziporyn, PhD of Start School Later, regarding school start times.
Are teenagers getting sufficient sleep?
Currently, there is a teen sleep epidemic. Studies have shown that two-thirds of high school students get under eight hours of sleep on school nights. Nearly 40% report getting six hours or less. Sleep loss increases as students progress through high school, with students from minority, urban, and lower socioeconomic households affected disproportionately.
How much sleep do teenagers need?
Most teenagers need about nine to nine-and-a-half hours of sleep per night for optimal growth, development, and functioning. Individual needs vary, but most require between eight and ten hours. Quality, timing, and regularity of sleep also matter.
During puberty, there is a delay in the circadian rhythm of about two to three hours. This makes it difficult for most teens to fall asleep before 11 p.m. or wake before 8 a.m. There is also a reduction in the homeostatic drive to sleep, or the ability to resist falling asleep the longer you are awake.
What do school start times have to do with this?
Many factors harm adolescent sleep, including biological changes,social demands, and individual behaviors. Teenagers also experience late-night extracurricular activities, homework deadlines, part-time jobs, and social interactions. All are difficult if not impossible to address on a large scale.
However, early school start times could be adjusted to impact the wider population. The problem is that current school hours do not allow most teenagers to get sufficient or appropriately timed sleep. Many high schools and middle schools in the United States have a start time in the 7 a.m. hour, with bus pick-ups as early as 5:30 am. Some students, who generally cannot fall asleep before 11 p.m., must wake as early as 4:30 or 5 a.m. This not only cuts sleep short but shortchanges the REM (rapid-eye movement) sleep considered critical for emotion regulation and memory consolidation. REM sleep is concentrated in the early morning hours.
If school starts later and extracurricular practices are moved to the morning, doesn’t this defeat the purpose of a later start?
Students who practice in the early morning will not necessarily benefit on the days they practice, but the school population as a whole benefits. Ideally, practices would be after school. Extracurriculars are optional, so students can always choose not to participate. One student choosing to participate in an early morning extracurricular is not an excuse for forcing this decision on the entire school population.
If school starts later, won’t teens just stay up later—essentially getting the same amount of sleep?
You’d think so, and this is one of the most common questions we’re asked. It is also a huge misconception. Study after study has shown that when school starts later, more students get more sleep. Most of that extra sleep comes in the morning while bedtimes stay about the same. This shouldn’t be surprising when you consider how late teenagers already go to bed.
Of course, students still need to follow healthy sleep practices. Starting school later does not guarantee that students will get more or better sleep, but not starting school later guarantees that most will not.
What are the outcomes of a later school start time?
Abundant evidence confirms that when schools move bell times later, more students get more sleep. The American Academy of Pediatrics, American Medical Association, and many other health organizations recommend that middle and high school classes start no earlier than 8:30 am. Studies consistently associate later school start times with more and better-timed sleep for adolescents, as well as fewer signs of depression, less stimulant and illegal substance use, and lower car crash rates, as well as significant improvements in attendance, truancy, tardiness, suspensions, and graduation rates.
If the evidence is so clear, why don’t all secondary schools start later?
Community life revolves around school hours. Concerns about how changes may impact transportation, jobs, childcare, and other aspects of community life when schools propose changing schedules are understandable. However, the hundreds of districts that have delayed bell times have repeatedly shown these concerns to be non-existent, overblown, temporary, or resolvable. People and communities can and do adjust. Low and no-cost transportation options can be found, too. The key is prioritizing student health and well-being, understanding and respecting sleep, and working together to come up with creative solutions.
The true obstacle is change which is always hard, even when it’s for the better. We’ve never seen a community that followed best implementation practices return to early start times. Plenty of school leaders say that if they ever suggested going back their communities would revolt.
“The best preparation we can give students is the rest they need for healthy growth, development, and learning.” - Terra Ziporyn
Terra Ziporyn, PhD is the Executive Director and Co-Founder of Start School Later. She is a science writer, novelist, and public health advocate.