This piece first appeared on Usable Knowledge, from the Harvard Graduate School of Education.

Thirty years ago, Ted Sizer, former Harvard Ed School dean and founder of the Essential Schools movement, described a typical public school schedule as “a series of units of time” where “the clock is king.”

School days had a “frenetic quality . . .  a sense of sustained restlessness,” he wrote in Horace’s Compromise, imagining the life of a high school student named Mark. “Mark is buffeted between classes in a tidal rush that sweeps him through till the last bell. Mark is known a little bit by a number of people…[but] No one may know him as a ‘whole person’ - unless he becomes a special problem or has special needs.”

It’s as if Sizer was describing my public high school in 2016.

Each day, I teach 130 students in a revolving door of classes. There is no passing time (one class ends at 8:45, the next begins at 8:45), few breaks (either for my students or me); and hardly a moment to catch my breath.

One boy seems upset, but the bell rings and 20 students are filing into class. He has to rush to avoid being marked tardy. A girl wants to continue our discussion about 19th-century tenements, but there simply is no time. As teachers, we learn to counsel on the fly. I come early and stay late, and in this way, I extend whatever conversations I can.

Classes lose their cadence, and their rhythm; reflective discussions and debates are jarringly interrupted by school bells that silence a student’s closing comment on labor strikes or leave unanswered a question about the differences between representative and direct democracy.

A side note: It is not only the bells that punctuate classes, but a cacophony of PA announcements, ringing classroom phones, or security staff coming to pick up a child - all of which succeed at throwing a lively class discussion to the winds.

In Building a Better Teacher, Elizabeth Green documents how Japanese education researchers studying American school classes in the 1990s were shocked by the quantity of interruptions American teachers endured; they found that almost a third of classes were thus interrupted.

Some historians peg the origins of our style of schooling to the “factory model” approach that Horace Mann brought back from Prussia in the mid 1800s. But whatever the origin, it’s time to scrap the traditional school schedule of a breathless string of 50-minute blocks, discrete and disconnected from one another.

Let’s re-envision the school day. Here are three ways we could start:

Take a break

In Finland, every hour of teaching is punctuated by a 15-minute break (in contrast, my students have a single 25 minute break, for lunch, in a nearly 7-hour school day). Children need this time to recharge and refocus (adults need it too). Simple breaks from concentrating are important for long-term learning, as the University of Minnesota’s Anthony Pellegrini has shown in his work on the importance of play and the role of recess.

Integrate the disciplines

In the professional world, our work must integrate disciplines - small business owners, nonprofit leaders, and scientists must combine skills in organization, finance, writing, and so much more. Schools should reflect the fact that skills are deployed in combination. And luckily, some are trying.

At the High Tech High network of California STEM-based charter schools, academic subjects break free of traditional boundaries.

Most students spend the first four periods of the day in interdisciplinary classes. One class is divided between two teachers: one teaches integrated math and science for two periods to half the students, the other teaches history and English. Then they swap students.

Sometimes they go further still, taking down all partitions - quite literally, removing a dividing wall that separates the two classes, and the two teachers embrace a range of subjects, with everyone working together. The results can be extraordinary, with students creating in-depth projects that weave together English, science, math, history and the arts.

In 2010, 10th graders at High Tech High in San Diego created a book of economic terms. Each student was in charge of a term: elasticity, moral hazards, opportunity cost, the invisible hand, predatory pricing. Over the course of a semester, they developed a mathematical representation of their term, created a graphic interpretation through a linoleum block print, and researched, wrote and edited an article about a contemporary issue that could be better understood by using their economic term. At the end, each student had to teach the term to their peers.

What if more classes and projects looked like this?

Wake up late

My morning classes are routinely filled with bleary-eyed, yawning students - and our school starts comparatively late, with first bell at 7:50 a.m. But a growing body of research from institutions including the CDC, the American Academy of Pediatrics, and the National Sleep Foundation [PDF] has found that early start times are deeply unhealthy to our students’ bodies and minds.

As teenagers grow, their sleep cycles shift as much as two hours later. The result is that on average high school students get only 5-6 hours of sleep, when to be healthy and ready to learn they should be getting 8.5 -9.5 hours. Lack of sleep is dangerous for teens, leading to increased rates of depression, drug and alcohol abuse, suicidal tendencies, and car accidents.

Shifting school start times back by just an hour could have an enormous impact on the health of our students, and also their academic success. One study documenting schools that made this shift found that 60% of students were able to get at least eight hours of sleep and that both attendance rates and standardized tests scores went up.

These are just a few of the many strategies schools are experimenting with, across the country, as they try to buck an absurdly outdated system. But alongside these strategies, we’ll need effective methods of introducing and implementing them across all schools. It’s my hope that in another thirty years, Ted Sizer’s description of high school will finally seem outdated.

Jessica Lander is a high school teacher - follow her on Twitter at @jessica_lander. 

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