When my daughter Sage was in 5th grade, she came home from school in tears. She had just learned that she wouldn’t be able to take orchestra, art, or foreign language in middle school. Instead, she and her classmates would have to spend 180 minutes every day in a new reading program the district was imposing to boost standardized test scores.
“Are you just going to cry?,” I asked her. “Or are you going to do something?”
Sage chose to do something. The petition she and her classmate presented to the county school board led to a broader community coalition and, eventually, a formal appeal to the state board of education, which unanimously ruled that the county was violating state regulations. Sage later became the student member of the countywide school board, and our family began years of educational activism, including the fight for healthy school start times.
That early lesson—the value of taking action over hand-wringing and tears—still resonates. Unfortunately, many school districts have responded to start-time policies with more crying than doing. But one California district instead chose to act. And it worked.
Their experience showed, concretely, that schools can find schedules that let students get healthy sleep without upending civilization. And it showed that they can do so cost-effectively—sometimes even saving money in the process.
What We Still Didn’t Know
Many school policymakers claim to “understand the science” supporting later start times. Yet they insist that they cannot find feasible, affordable ways to start schools at times compatible with healthy sleep—despite hundreds districts that already have.
These kinds of claims are exactly what crippled Florida’s recent bill setting a floor on how early middle and high schools could start. No one who had done their homework argued the idea was unsound. But plenty argued that starting schools at sane, humane times was as practical as curing cancer. Great idea. But a dream.
California heard similar objections when its 2019 law required high schools to start no earlier than 8:30 a.m. and middle schools no earlier than 8 a.m. So it’s no surprise that we at Start School Later are constantly asked how things have gone and whether we have any data yet.
Some things didn’t require more evidence. We already knew that too‑early start times were harming students. We already knew that communities with the will to change could do so in feasible, affordable ways. And we already knew that when districts followed sound change‑management practices, students slept more and often saw improvements in health, safety, and school performance. That evidence was a major reason the law passed in the first place.
What we didn’t know was how well a statewide floor on start times could be implemented in practice—whether districts would use the opportunity to help students get healthier sleep or simply comply on paper. That’s why Start School Later convened a research summit at Stanford in 2021 to identify “relevant, refined, and innovative” research needs during the law’s three‑year rollout. Participants surfaced many open questions, including:
how commute times and before‑school activities affect sleep
how school hours influence equity gaps, youth crime, and athletic performance
whether season and geography shape outcomes
what effective implementation actually looks like
Yet until recently, the only “research” out of California involved anecdotal opinions rather than objective or long‑term outcomes data. This has finally started to change with the release of a new econometric analysis that I’ll discuss in a subsequent article. But for the first few years after the law was passed, all we had were anecdotes—and a steady chorus of claims that starting school at safe, healthy hours was simply too hard and too expensive.
The District That Chose Solutions Over Excuses
San Francisco Unified did something different. Instead of complaining, the district turned to a team of operations experts from the Yale School of Management, Georgia Tech, and Northwestern for help.
That team built a novel tool that lets districts explore thousands of feasible bell‑schedule scenarios, visualize trade‑offs, and balance constraints like bus and driver availability, family needs, and equity considerations. Rather than prescribing a single “optimal” schedule—as many districts still do—the tool supported consensus‑building by showing stakeholders how different choices affect costs and logistics.
The team was acutely aware of the need to make community engagement a central part of the process. Two of them had previously helped design an algorithm for Boston Public Schools that produced technically efficient but socially disastrous start‑time changes. The problem wasn’t the technology or the goal of later high school start times. It was the district’s lack of transparent communication, stakeholder involvement, and thoughtful change management.
Learning from that failure, the team created what they describe as the first “interactive, optimization‑driven” start‑time redesign for SFUSD. Their approach uncovered options that maintained—or even improved—transportation efficiency while shifting many schools to later, developmentally appropriate start times. From the outset, they involved community stakeholders, making both the trade‑offs and the benefits visible and understandable.
The result? In August 2021 SFUSD was able to comply with the state law across 133 schools and saved over $5 million annually in transportation costs—money it reinvested in classrooms.
Ending the “Too Hard, Too Expensive” Narrative
This novel approach should take the wind out of the naysayers’ sails. It is a genuine gamechanger for districts who until now could simply claim that changing schedules is just too complex, too disruptive, and/or too costly.
The approach is not only remarkable in its computational power to generate options but in its ability to make complex decisions transparent, collaborative, and politically viable. And more powerfully than any prior claim or study, it formally and clearly demonstrates that the constraints that supposedly force districts to retain unsafe, unhealthy start times are far more flexible than often asserted, that change can be cost-neutral or even cost-saving, and that involving stakeholders in the change process and using optimization tools to make trade-offs transparent improves community buy-in.
Nothing about these conclusions is new. For years we have argued that districts must question long‑held assumptions, rethink priorities, and use structured, constraint‑based reasoning to redesign transportation systems. What’s new is the validation: real-world proof in a large, complex school system along with a scalable, user-friendly, and publicly available tool that any district can tailor to their needs. And, excitingly, the research team says they may formalize the process if more districts express interest.
The findings also reinforce themes we’ve seen for years: the biggest barriers to humane school start times are rarely logistical or even financial. Rather they are the difficulty of building community consensus for largescale systemic change—and, more specifically, the difficulty of overcoming political pressures and long‑standing beliefs about what is and isn’t possible or necessary.
Lessons for School Policymakers
School leaders and legislators considering later start times would be wise to look closely at this study. For one thing, it provides strong ground for questioning astronomical cost estimates they’re so often handed, estimates that, whether or not they turn out to be straw men, are by no means the only thing stopping change. A bigger obstacle is a lack of political will, rooted in human fear of change, failure of imagination, and misconceptions about sleep—and for districts that have this will, findings from this study should give leaders a better opportunity to lead.
The study also underscores why state laws regulating school start times must ensure that districts can avail themselves of the resources available to help them comply successfully—this kind of tool being a prime example. Future state school start time laws might recognize the burden placed on districts to figure out compliance on their own, and instead include funding or other supports to help school leaders navigate the complex and politically charged task of changing school hours.
But the number one lesson here is that state laws setting parameters on school hours are not unreasonable, nor should they be construed as crippling unfunded mandates for school districts. This study shows that real tools, real expertise, and real experience already exist to help districts get this done. And it offers a counterweight to show-stopping claims about how impossible and expensive it is to change.