By starting school too early, New York City is depriving students of desperately needed sleep. The ripple effects are enormous.
In New York City, schools must meet class size requirements, monitor air quality for outdoor activity, provide universal free lunch and enforce strict rules for lead and asbestos remediation. But even with this broad architecture of protections, the City overlooks some of the simplest and most consequential levers it has to improve student health, safety and well-being. One of the clearest examples is school start times.
Unlike class size, nutrition or environmental hazards, the timing of the school day has no citywide guardrails designed for students. While adult workdays are strictly defined and negotiated through the teachers contract, there are no parallel protections for adolescents, whose biological sleep needs are far more sensitive to schedule timing. Instead of being guided by health standards, start times are dictated by labor parameters and logistical negotiations. Within those adult-focused constraints, schools too often require students to be at their desks at hours that directly conflict with their biological sleep needs, with no required consideration of commute length. This oversight has allowed some schools to shift start times even earlier in recent years, even as decades of research show that early start times harm adolescent health, safety and learning.
Why sleep (and school start times) matter
Sleep is foundational to growth, development and just about every aspect of human health and function — especially for growing bodies and brains. Rapid physical maturation, expanding cognitive demands and heightened emotional reactivity in adolescence make sleep critical in these years. And beginning at puberty, a two- to three-hour delay in the sleep cycle — a temporary change also observed in other mammalian species — makes it physiologically difficult for most adolescents to fall asleep before 11 p.m. or wake before 8 a.m.
No amount of good sleep habits can reliably overcome this biological delay. Of late, we’ve seen growing awareness about the need for young people to stay off screens after a certain time in the evening, but this is like putting a Band-Aid on a gaping wound. When adolescents are required to wake during their biological night, they experience insufficient and poorly timed sleep that is consistently linked to higher rates of depression, anxiety, suicidal ideation, substance use, drowsy-driving crashes and impaired metabolic and immune function.
Early start times magnify these problems in students from vulnerable socioeconomic backgrounds, who already experience worse sleep health due to environmental stressors, inconsistent schedules and nighttime responsibilities. Research consistently shows that when schools start later, students from lower-income families benefit disproportionately in attendance, academic performance and graduation rates.
As is, New York City teenagers are doing their part to keep the “city that never sleeps” tradition alive. Mirroring national data, about 75% of the city’s adolescents get insufficient sleep on school nights, according to a New York City Department of Health report, and nearly half get six or fewer hours.
School start times are by no means the only contributor to these statistics, but they are a major and remediable structural factor — and one that we control for all students. In fact, delaying school start times is the only measure proven to sustainably improve adolescent sleep health at the population level.
Outcome studies consistently show that when schools start later, adolescents get more — and better-timed — sleep, and the effects of this extend across health, safety and school performance, including lower rates of depressive symptoms, less substance use, fewer motor-vehicle crashes, and measurable gains in concentration, attendance, grades, graduation rates and disciplinary outcomes, with particularly strong improvements among vulnerable populations. In a landmark Seattle study, for example, students slept an average of 34 minutes more per night after start times were shifted later and showed measurable improvements in attendance and academic performance.
The politics of the school clock
The evidence showing the harm of too-early school start times and the benefits of later ones is so compelling that many major health and education organizations — beginning with the American Academy of Pediatrics in 2014 — now recommend that middle and high schools start classes no earlier than 8:30 a.m. These recommendations are based on Mary Carskadon’s seminal “perfect storm” model of adolescent sleep, establishing that most adolescents need 9-9.5 hours of sleep per night and struggle to fall asleep before 11 p.m. for physiologic reasons, and assuming that they can get from beds to classrooms in under an hour.
Across the country, however, districts have struggled to change schedules. The obstacle has not been unclear evidence but, rather, school politics and logistics. School hours are entangled with transportation systems, athletic programs, afterschool activities, childcare needs and long-standing community routines. Leaders know that altering school hours can provoke intense pushback from families and staff who fear change will disrupt their lives.
Resistance to change is to be expected, but experience from more than 500 districts shows that many anticipated problems prove to be unfounded, overblown, temporary or readily resolved. Some states — most notably California — have enacted statewide legislation setting guardrails on how early middle and high schools can start class. And despite predictions that the law would be unworkable, large urban districts, even those like San Francisco that had to reroute transportation systems, have found feasible and sometimes even cost-saving solutions.
Why New York City is primed for change
New York City is, in many ways, the easiest large district in America in which to change school start times. Unlike suburban systems, the City does not rely on complex yellow-bus routing for most students. Schools set their schedules independently, and students in grades 7-12 overwhelmingly commute on their own using public transportation. The usual suburban objections — parents needing to drop children off before getting themselves to work, buses that cannot run later, or teenagers needing to pick up younger siblings — simply do not apply. The only real constraints are state regulations mandating 990 hours of instruction over 180 days for secondary students, and the United Federation of Teachers (UFT) contract explicitly defining a 6-hour-and-20-minute workday that cannot begin before 8 a.m. without a formal modification process.
In 2019, City Councilman Mark Treyger introduced legislation to study pushing back middle and high school start times to at least 8:30 a.m. At the time, most schools started between 8 and 8:20 a.m., and roughly 50 started even earlier, according to a WPIX11 report — forcing kids to cut their sleep short on a daily basis. The bill was inspired by Seattle’s success, and Department of Education officials testified that a pilot program at five schools had already produced improvements in attendance, lateness and student performance. Yet the bill went nowhere. Statewide efforts have also stalled. Legislation that would prohibit middle and high schools from starting before 8:30 a.m. and elementary schools before 8 a.m. has been introduced repeatedly without advancing.
Meanwhile, some city schools have quietly shifted earlier, particularly middle schools. Families often do not realize that start times matter, or that they have changed, until their children begin struggling with morning wake-ups, tardiness or declining engagement.
New York’s vast school choice network compounds the problem. Although the UFT contract provides a valuable buffer that keeps most schools from starting before 8 a.m., times still easily creep to 8:10 or 8 a.m. Such shifts might seem trivial but can translate into 6 a.m. wake-ups for students commuting 60-90 minutes each way from the Bronx to Manhattan or Queens to Brooklyn, making a full night of sleep mathematically impossible. Similar transit realities have prompted other urban districts to consider 9 a.m. guardrails.
Early start times also push students onto public transportation in the dark, especially in winter. And for many middle and high schoolers, especially in underserved communities, earlier school hours translate directly into longer stretches of unsupervised time after the school day. Afterschool programs are often golden time for privileged students — but many underprivileged young people in New York City don’t have access to them. According to the Afterschool Alliance, the unmet demand for afterschool programs in New York leaves nearly 1.4 million children and youth without access. The New York City Comptroller’s Office reports that despite the City spending more than $450 million annually on afterschool programs, many schools still cannot offer enough free, high-quality seats, leaving working families without needed care and enrichment. This means early dismissal disproportionately harms the very students least likely to have structured afterschool options.
Despite these hurdles, New York City is primed for change. There are already mechanisms in place that allow individual schools to shift their schedules. Several schools — including Bard High School Early College, Essex Street Academy and various alternative programs — start at 9 a.m. or later. The system is also capable of setting rigid parameters around time, as seen with strict state instructional mandates and contractual limits on the adult workday. The bureaucracy knows exactly how to regulate the clock for funding compliance and adult negotiations. It simply hasn’t set parameters to protect the biological needs of its students.
We cannot guarantee that every child will get healthy sleep; some will always face early commutes or family responsibilities. But we can guarantee that school schedules do not structurally deprive students of the opportunity for healthy sleep. A practical policy would set 8:30 a.m. as the earliest required attendance time for middle and high school students, incorporate commute realities into scheduling, expand flexible options such as early online classes or flex periods and treat sleep health as a basic safety standard — no different from asbestos removal or safe drinking water.
Healthy school hours should not be a luxury for the few; they should be treated as a nonnegotiable health and safety standard for all. Large, complex urban districts have done it. Entire states have done it. New York City can do it too.
