° Сalifornia teens could age a little later this year thanks to newly introduced law it says that most high schools and middle schools cannot start before 8:30 a.m. and 8 a.m., respectively.
This law — the first in the country to set statewide mandates for school start times — is important not only to California students but also to public health experts who are fighting what the American Academy of Pediatrics (AAP) has called ‘epidemic’ of teenage sleep deprivation. Both AAP and US Centers for Disease Control and Prevention have long opposed morning classes and advocated for middle and high school bells no earlier than 8:30 a.m.
Delayed school start is an attempt to help teenagers sleep morewhich research shows is a big problem in the U.S. Only about 30 percent of high school students get the recommended eight hours of sleep on school nights, according to the CDC data. Studies suggest sleep deprivation may put teenagers and young adults at increased risk for obesity, substance use, depression, and poor academic performance, among other issues.
Research has long shown this circadian rhythms—light-mediated internal cues that help regulate sleep—change across the life cycle. This is partly why adults can naturally get up earlier with age. Meanwhile, teenagers’ body clocks are like that best timed with bedtimes around 11pm or midnight and a wake-up time about nine hours later—a schedule that’s impossible when classes start before 8 a.m.
Early School Schedules are largely a holdover from a time when most families didn’t have two working parents and therefore didn’t have to worry about sticking to a 9-to-5 schedule. Juggling bus schedules, classes, athletics, and other extracurriculars drives the bells to ring early.
But these schedules are not based on science. A mismatch between teenagers’ internal rhythms and external schedules sets them up for failure, studies have long suggested. One document from 1998 found that when a small group of students started school about an hour earlier than before, they experienced “significant sleep deprivation and daytime sleepiness.”
Moving the start times back has been shown to backfire. A 2002 study conducted five years after seven Minneapolis public high schools changed their start times from 7:15 a.m. to 8:40 a.m. found that the change allowed children to sleep about an extra hour a night; students also reported better attendance and fewer symptoms of depression. In a 2010 studyresearchers studied students at a Rhode Island high school after it moved its start time from 8 a.m. to 8:30 a.m. and found that students got an extra 45 minutes of sleep a night while reporting less fatigue and better mood.
More recently, a study published in 2021 found that significantly more Denver-area middle and high school students got enough daily sleep after the local school district delayed start times by 40 to 70 minutes. Another 2021 study on Colorado students found that those who started school before 8:30 a.m. were slightly more likely to attempt suicide than peers who started later, although the results were not statistically significant. Although more research is needed and many confounding variables may cloud the relationship, the findings suggest that starting classes later may improving teenage mental health.
But changing the time of the bell is not a panacea. February 2022 Research Review who examined the links between later start times and academic achievement found mixed results, with some schools reporting positive effects and others reporting negative or unclear effects of the change.
There are also a lot of logistics to contend with. In 2016, Durham, North Carolina Public Schools moved their start time from 7:30 a.m. to 9 a.m. in research conducted the following year, only 26% of school staff said children were better rested and only 14% said they were learning more. Only 13% of school staff and 27% of parents want to keep the new schedule. Why? The drastic change meant the school day ended later, pushing extracurriculars, after-school work and homework later into the evening and sometimes keeping children up well past the previous bedtime.
In 2018, schools in Newport, Rhode Island, returned to their original start times after a two-year experiment with later bells created a number of logistical headaches, including difficult coordination with nearby schools and scheduling after-school hours. Transportation can also be an issue, whether it’s changing bus schedules, struggling with traffic patterns, or finding ways for working parents to drop off their kids later in the morning. some schools have learned by moving their schedules later.
California teacher Jeremy Adams raised many of these concerns in January Mud matters op-ed, adding that the new state law will inconvenience teachers who must remain on campus for extracurricular activities that begin after the school day ends. “Ultimately,” Adams wrote, “this law will become a case of ‘unintended consequences.'”
The school start time debate is still an area of active research. A team in Colorado, for example, study how changing school start times affects not only the health of students, but also that of their families, teachers and the wider community. And all eyes will be on the statewide change in California, like education researcher Deborah Temkin said NBC News after the policy was first passed in 2019. “If this turns out to be successful, with relatively few consequences, then I think it’s something that other states will probably consider,” Temkin said.
Since the school year is just starting, it’s too early to tell how the experiment will play out. But like some California high school students said on Mercury News, it will take more than a later start to cure their fatigue. “When you’re in high school, no matter what time you wake up, you’re going to be tired,” senior Annika Bose said. “At least now I have time to grab a coffee before class.”
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