How Many Schools Have Moved Start Times Later?

The number one question people ask us at Start School Later involves how many schools have "made the change." Unfortunately, this question has no simple answers.

Sleep experts, pediatricians, psychologists, educators, parents, and students have been pushing to delay the start of the secondary school day for decades. Until the last quarter of the 20th century, classes rarely began before 8:30 or 9 a.m., but today many begin much earlier, with a sizable minority requiring students to be in class around 7 a.m. or even earlier, making it nearly impossible for many adolescents to get enough or appropriately timed sleep.

Has there been any progress? The most obvious way to answer this question would be by looking at the number of schools that have delayed bell times. But it turns out that answering this question is perhaps even more challenging that getting schools to change their schedules.

On an anecdotal level, Start School Later maintains a list of known success stories, case studies, and local initiatives as we become aware of them. Other organizations, including the website SchoolStartTime, the National Sleep Foundation (decades ago), and our Pennsylvania chapter, have attempted to do the same thing. However, all these lists have serious limitations, and most reflect “catch-as-catch-can” findings by volunteers and/or a single moment in time. Alas, no better lists exist.

What We Know (Not Much)

What we know about school start times come largely from two major national surveys conducted by the US Department of Education’s National Center for Education Statistics (NCES): the Schools and Staffing Survey (SASS) and its successor, the National Teacher and Principal Survey (NTPS).

The SASS was conducted on nationally representative samples of U.S. school districts, schools, and staff at various intervals between 1987 and 2011, and the NTPS between in 2015-2016, 2017-2018, and 2020-2021. Data from these surveys allows us to estimate the percentage of middle and high schools that start in various time windows (e.g., before 7:30 a.m. or after 9 a.m.), as well as average starting times in schools with varying demographic characteristics. It also suggests trends in these averages since 2007, the first year in which the SASS included a question about start times.

Asking “how many school have made the change” is essentially meaningless. Made what change exactly? A change to “later” start times, presumably. But “later” is a relative term.

From these data, we know that the average bell time of US high schools has not changed significantly since 2007, the first year this statistic was recorded. We also know that close to 83% of US middle, high, and combined middle/high schools in the USA still start class before 8:30 a.m., and that in most states, over 75% of middle, high, and combined schools start before 8:30 a.m.

These surveys are only done every few years, and the last one was done in school year 2020-21—not exactly a representative year. With the COVID-19 pandemic raging, many schools that year offered only virtual, or hybrid classes, very few of which started at 7 a.m. Public schools offering only distance-learning instruction because of COVID-19 had considerably later average starts (8:21 a.m.) than those offering a hybrid of in-person and distance-learning instruction (8:11 a.m.) or only offering in-person instruction or pre-pandemic schedules (8:09 a.m.). Among private schools, those offering only distance-learning instruction had a later average start time (8:24 a.m.) than schools offering a mix of in-person and distance-learning instruction (8:11 a.m.) or instruction only in-person or unchanged from pre-pandemic schedules (8:12 a.m.).

So we can hardly take the data from that latest survey as representative of ongoing trends, especially since many schools reverted to very early start times when they returned to in-person schooling.

Limited (and Dwindling) Data

A comprehensive and meaningful list of schools that have delayed bell times to give adolescents better opportunities to get adequate sleep—or even for other reasons—is not likely in the foreseeable future. Part of the problem is that there are over 13,000 individual school districts in the USA, and about 40,000 individual middle and high schools. These districts and schools change their hours all the time, at will, earlier as well as later, for a variety of reasons.

Making matters worse, education in the United States is highly decentralized. There is no single or unchanging way that the 100,000 or so individual schools in this country order their days, or many other things for that matter. Nor is there a centralized clearinghouse with disaggregated data that tracks schedule changes by individual school or district over time. As a result we cannot tell if individual districts or schools retain their changes as the years go by, but only if the average start time in sampled schools has changed.

Nor do current lists allow us to determine commute times or zero-hour classes and practices (which can undermine later start times) or how many districts moved high school times later while moving middle school times earlier, an all-too-common occurrence. And with current efforts to dismantle the US Department of Education, our hope of getting such information is receding.

Even if we had such a centralized clearinghouse, moreover, we still would have no way to know why schools changed their hours. The “why” isn’t always sleep health. Financial, pedagogical, or logistical factors also often underlie school start-time changes, and sometimes it is hard to differentiate the public reasons from the real ones.

Of course, later start times for whatever reason still benefit student sleep and well-being, but they also run the risk of reversal when budgets, educational philosophies, or community demographics shift. What doesn’t shift is the biological need for sleep, and until schools set schedules by formally recognizing this need, and setting policies to respect it going forward, it’s hard to claim they have “made the change.”

A Meaningless Question?

Clearinghouses aside, asking “how many school have made the change” is also fundamentally meaningless. Made what change exactly? A change to “later” start times, presumably. But “later” is a relative term. Do we only count schools that made it to 8:30 a.m. or later? What about schools that moved to 8:20 or 8:25 a.m. from grueling 7:15 or 7:30 a.m. starts? And what about schools moved only from 7:17 to 7:30 a.m. but did it as a first step, or with the knowledge that every little bit helps?

It gets even more complicated. Do we count districts that moved some but not all schools, or the ones that are piloting a later start and awaiting on a final decision? Do we count the schools that moved “later” but did it to save money or accommodate redistricting rather than to respect student sleep needs? Do we count schools that never moved earlier than 8:30 a.m. in the first place, or districts that moved high schools later while moving middle schools earlier? What about districts that moved high schools later but reverted to earlier hours ten years later when everyone forgot why those later hours mattered?

Without nailing down consistent answers to these questions, it is impossible to answer questions about the number of schools that have delayed start times. And the more nailing down we do, the slimmer the supply of available answers—because the data available on school starting times does not include these kinds of nuances.

Alternative Measures of Progress

Ideally, we would like to see a national or even statewide database in which both school start time and bus time data are collected annually and made available for analysis by individual school and district over time. We still would lack more nuanced answers about why most schools are changing or keeping their hours, but we would know a lot more about general trends as well as changes over time in individual communities.

Over the years, various sleep researchers, have attempted to collect such data and abandoned the effort when they realized the magnitude of the task. Start School Later does not have the resources to do this either, and groups with the resources thus far have not had the motivation to collect it. One of our goals, however, is to get state or national agencies to collect and disseminate this very data (or get a grant to do it ourselves!) because that in and of itself would work wonders in raising awareness about the nature of the problem. At this point even keeping the old, flawed NCES data collection alive would be welcome.

Both state and local policies to ensure later school start times have already vastly improved the lives of millions of children.

Meanwhile, there are many alternative ways to assess the growth of the start school later movement. These include the growing number of position statements issued by major health, education, and civic organizations recommending later, healthier, safer school start times. These organizations include the American Academy of Pediatrics, American Medical Association, American Psychological Association, American Academy of Sleep Medicine, National Sleep Foundation, National Education Association, and the National PTA.

Another sign of progress is the explosion in media attention in the past decade or so to adolescent sleep and school start times, documenting schools and districts throughout the world deciding to delay start times or seriously considering doing so. Also encouraging is the growth of Start School Later itself—as marked not only in the growing number of volunteer-led chapters, but also in increasing visits to our website and social media channels. Accelerated interest and support for start-time change led to unprecedented 2017 and 2024 national conferences that brought together the worlds of health, sleep research, education, policy, and advocacy and facilitated coalitions and policy initiatives across the country.

Finally, the many local success stories we encounter every month combined with the growing volume of school start time legislation in many US states is a sure sign of progress. Since 2014 state lawmakers have introduced bills related to adolescent sleep and school start times in at least 28 US states, with 12 of them—including California’s groundbreaking legislation setting a floor on how early schools open—signed into law. Counting the precise number of schools that have “made the change” continues to be a challenge, but unquestionably these many state and local policies to ensure later school start times have already vastly improved the lives of millions of children across the nation.