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We register the pain of burning when our skin touches surfaces hotter than 111 degrees Fahrenheit.
Students at Oakland’s International Community School gather data about heat risk on their playground.

Prolonged contact with a 118-degree surface puts us at risk of first-degree burns. At 130 degrees, a second-degree burn can happen in under ten seconds.

Around noon on a sunny day in late October, three students stood in a tight circle on the yard at International Community School in Oakland, California. “109!” yelled a fifth grader named Emmanuel, pointing a surface temperature thermometer at the concrete under his feet. He walked over to the jungle gym and aimed the device at the plastic slide. “115!”

As his classmate Angelica recorded the measurements on her clipboard, another student, 10-year-old David, studied a map of the schoolyard and then sprinted across a wide stretch of asphalt to the next spot to take a reading. There, in the shade of a lone tree growing a few feet outside the fence line, he pointed his device. “72!” he yelled, reading the thermometer’s digital screen.

At recess the big yard was a sea of activity. Kids were swinging, sliding, tagging, and climbing, while a few adults with whistles around their necks kept an eye out from the perimeter. Every few minutes, a commuter train screeched through the elevated rail line paralleling Interstate 880, across a busy street from the school. It was a beautiful Bay Area autumn day, not a cloud in the sky, just 63 degrees. But despite the mild weather, the parts of the playground sitting in direct sun were almost hot enough to be dangerous.

And here—like many sites throughout Oakland Unified School District—almost every part of the playground sits in direct sun. “There are only like two trees here,” says David. “It gets pretty hot when we’re outside all recess.” On one hot day a few weeks earlier, students measured surface temperatures on the yard as high as 132 degrees.

“Right now it’s like: concrete, concrete, concrete,” says Principal Eleanor Alderman. “At recess I get kids crowded around the door to my office, because it’s one of the only places on the yard with shade.”

Angelica, David, and Emmanuel were gathering data to inform some important choices: exactly where to plant more trees, swap hot concrete with soft grass, and build garden beds to grow fresh vegetables. The yard at International Community School is one of the first in Oakland The Trust for Public Land is helping to transform throughout the city, part of an effort to remake asphalt yards nationwide into cool, green places to play and learn.

“The default for schoolyard design in America is pavement,” says Sharon Danks, director of the nonprofit Green Schoolyards America, a partner in The Trust for Public Land’s Oakland program. “And as the climate continues to warm, the need for more green space in our cities—anywhere we can put it—only grows more urgent.”

A group of kids are laying on the ground with pencils.

Striding down the long main hallway at International Community School in dark jeans, colorful tattoos extending beyond the cuffs of her gray blazer, Principal Eleanor Alderman is a walking, talking command center. 

She stops to chat with the janitor about an upcoming community event, switches to Spanish to take a call from a parent on her cell phone, then puts her hand over the receiver to slow two boys who probably didn’t expect to encounter their principal as they sprinted through the doors at the end of the hall.

Alderman can talk at great length about the qualities that make the dual-language International Community School special. She mentions small classes helmed by deeply committed, veteran teachers who cover everything from gardening to capoeira to hip-hop dance to art. At least a third of the students have siblings at the school, and parents are attentive and involved in administrative decisions.

Since she took the head job here four years ago, Alderman has wished the school’s grounds better reflected and nurtured the community she’s worked so hard to build. “This is a high-need area for environmental health,” she says. “There are too few grocery stores, poor air quality, a lack of access to parks. The schoolyard is the only safe place for kids to play in the neighborhood.”

“This is a wonderful school,” says Sonia Escobar, whose daughter is in fourth grade. “We feel comfortable. We feel welcome. We feel loved. My kids are safe in this school.” But since her eldest son started here in kindergarten seven years ago, she has always worried about the playground. “Because it’s horrible. Especially when it’s hot weather, the kids are out there playing, they’re thirsty, there’s no shade,” says Escobar. “When I ask them, ‘How was your day, baby?’ They say, ‘Oh Mommy, it was so hot.’”

Two pictures of a basketball court and a playground.
The Trust for Public Land has transformed hundreds of schoolyards across the country into green, welcoming public parks.

Escobar is one of the many parents who’ve helped plan improvements to the schoolyard, which will likely go to construction this summer. “We’re going to get more trees, more shade, take away some of the concrete, I think, and make a soccer field,” she says. “We’re happy to have been a part of it, because we have to do something to help our kids.”

Burns from hot surfaces are just one unintended health hazard of the standard asphalt schoolyard design. “Our kids were coming home sunburned and dehydrated, even from just being out there for a short time at recess. They had headaches. We worried about heat stroke,” says Ricardo Cortes. He’s the parent of a kindergartener and a third grader at Melrose Leadership Academy in East Oakland. Cortes loves his kids’ school and says they’re getting a great education. But just like at International Community School, the yard at Melrose is mostly concrete, surrounded by a tall chain-link fence.

Cortes works as a policeman. “I’ve spent some time in prisons. When we first started at this school, I thought, ‘Oh my god, it looks like a prison,” he says. “We say we care for our kids? Why are we putting them on slabs of asphalt that get horribly hot, with nothing for them to do?”

Researchers are learning more about how rising temperatures will affect all aspects of our lives—including kids’ ability to succeed in school. A recent study from UCLA’s Department of Public Policy and the Luskin Center for Innovation found that every one-degree increase in average outdoor temperature over a school year reduces student performance on standardized tests by one percent.

So Cortes joined a group of Melrose parents who’d long been fighting for a safer, more engaging schoolyard. “The administration was very supportive of us getting involved, but they made it very clear they didn’t have the bandwidth to do anything—we were on our own,” says Kim Walker, who helped organize Melrose parents around this issue when her daughter started kindergarten nine years ago. “I understand! We’re pushing for significant changes, and the district is strapped. They can’t take it on alone either. This should be a concern for the whole community, and not just up to the school district, when public education is already struggling so much.”

Walker has had to dissuade parents who, at wits’ end, imagined scaling the fence under the cover of darkness and taking a jackhammer to the concrete.

“I understand their desperation, but we were able to work a little more systemically instead,” she says. Parents applied for grants and lobbied at the district and state levels. They gathered input from teachers, neighbors, and the community to create a playground master plan. And they devoted hours of their weekends to making what changes they could: building garden boxes, planting, watering, and weeding.

“We were like the sea hitting against the seawall trying to find a crack. We went years without much progress,” says Walker. “Until we got connected to The Trust for Public Land.”

Since 2017 The Trust for Public Land has been working alongside the Melrose school community to plan, fund, and build a greener schoolyard. “They gave us a big boost in terms of funding, technical expertise, and community organizing capacity,” Walker says. “They helped us take many more voices and perspectives into account.”

In late 2018, The Trust for Public Land completed the first phase of green upgrades at Melrose, replacing pavement with gardens full of native plants and planting 16 new trees that will grow to cover much of the yard in shade.

“The Trust for Public Land’s effort is a step in the right direction,” says Cortes. “But we still have a lot of work to do.” He means in terms of upgrades to his kid’s school but also a broader rethinking of schoolyard design, funding, and accountability. So much of the impetus for transforming the schoolyard came from parents like him—with the time and resources to get deeply involved for years at a time. “The way it is now, change only happens at the schools where parents can afford that level of commitment,” he laments. “That’s not right.”

Void of trees, grass, and shade, badly designed schoolyards—along with blacktop highways, dark rooftops, and other city infrastructure—trap heat from the sun, increasing temperatures throughout the entire neighborhood. This is known as the “heat island effect,” and it’s part of why cities are often much hotter than surrounding rural areas.

Even within a city, heat risk varies widely. Neighborhoods with more mature trees, bigger lawns, and green parks stay noticeably cooler than neighborhoods with more pavement, denser buildings, and less shade. The Trust for Public Land has mapped the heat island effect at a neighborhood scale for over 14,000 municipalities in the United States. On the map of Oakland, the neighborhoods around International Community School and Melrose Leadership Academy are dark red, indicating they’re among the hottest spots in the city.

“We say we care for our kids? Why are we putting them on slabs of asphalt that get horribly hot, with nothing for them to do?”

A skateboarder in a parking lot.

“In Oakland, there’s that hills-and-flats dynamic,” says Cortes. The city reaches from the ports and docks of the bay shore, across miles of coastal plains, and up the steep, forested front of the East Bay Hills. “As you go uphill, you notice the houses and trees get bigger. The schools don’t have fences around them. They have greenery. It’s literally cooler up there,” he says.

“In America today, wealth equals resilience,” says Matt Holmes. He’s director of Groundwork Richmond, a youth services and environmental justice nonprofit in Richmond, California, a city in the flats a few miles up the east shore of San Francisco Bay from Oakland. “We’ll see this [problem] exacerbated worldwide in coming decades, as temperatures rise. Wealth in the U.S. is created by home ownership—and access to home ownership is not equally distributed, and that is by design.”

Holmes is talking, in part, about redlining—the federal government’s practice in the mid-20th century of rating neighborhoods for mortgage lenders by “risk” of investing, largely based on the number of African Americans and immigrants living in a neighborhood. “The fact is that federal policy caused wealth to accumulate for the benefit of white people, at the expense of people of color,” says Holmes. “We are battling the effects of generations of discriminatory housing policies to this day.”

A recent study in the journal Climate found that across the country, redlined neighborhoods are hotter than their counterparts by an average of almost five degrees. The U.S. Forest Service led another study showing that predominately white neighborhoods have twice as many trees as formerly redlined neighborhoods.

“That extra heat can be the difference between discomfort and illness, or even death—especially for the elderly, kids, and people with existing health issues,” says Trust for Public Land Climate Director Brendan Shane. Extreme heat kills more people in America than any other weather disaster, and heat waves are growing in intensity and frequency as the climate changes.

The reasons for this green space disparity—everywhere from yards to sidewalks to parks and schoolyards—are many. “One result of that original sin of racist zoning is that white folks are much likelier to own their homes, and people of color rent,” says Holmes. “Landlords aren’t always in the business of maintaining outdoor properties. Trees lift up sidewalks, and a poorer city can’t afford to manage them. So rather than paying to keep trees healthy, landlords or city crews will cut them down.”

Well-designed schoolyards with plenty of trees and green space have the power to combat heat risk throughout the neighborhood. But schoolyards like this tend to be more expensive to build and maintain, explains Sharon Danks. And because public schools are funded in part by property taxes in America, access to all kinds of resources—from safe schoolyards to extracurricular activities—depends to some extent on the local tax base.

“Believe it or not, ours is a system that’s going to plan. This is not a system gone awry. We’ve set it up from the beginning to be unequal,” says Danks.

The Trust for Public Land has been helping schools make the most of their outdoor space for decades. From New York to Philadelphia to Dallas, the organization has transformed over 250 formerly asphalt schoolyards into green and leafy public parks. “There are over a hundred thousand public schoolyards in America, and every single one has the potential to address climate injustice,” says Alejandra Chiesa, Bay Area program director for The Trust for Public Land.

But in too many cities, badly designed schoolyards are actually making the problem worse, putting students at risk and contributing to higher temperatures throughout the neighborhood. The organization recently analyzed data showing that more than one-third of public schools in the U.S. are in a heat island.

“Public schoolyards are public land.”

Protecting people from the risks of a changing climate is one of the reasons The Trust for Public Land is sharpening its focus on transforming neglected schoolyards into greener, healthier hubs for the whole community. The organization is working with longtime experts like Sharon Danks and public agencies like Oakland Unified School District and the California Coastal Conservancy to advance policies and funding for green schoolyards.

“The physical environment at a school makes a huge difference for our students’ health—physically, socially, and emotionally,” says Michelle Oppen, wellness coordinator for Oakland Unified School District. In 2019, the district adopted a new policy outlining how it will build and maintain greener yards for every school, in every neighborhood.

In the next five years, The Trust for Public Land aims to build green schoolyards in 20 more school districts, using cutting-edge data and mapping to pinpoint the neighborhoods at greatest need for cooling infrastructure.

“Public schoolyards are public land. It is a misuse of our public land to not use every bit of it we can to protect people from climate risks,” says Chiesa.

Back at International Community School, Sonia Escobar’s daughter Allison is looking forward to seeing her schoolyard transform. “I’m always thinking to myself, ‘Oh this is going to be so fun. It’s going to be nice for a change!’” She’s a little sad that she’ll only be at the school for another year, before she heads off to sixth grade at a private academy in north Oakland where her mom has a job preparing food.

“The playground at my next school is amazing. They have two play structures, swings, tree houses, a place where you can build stuff out of wood, and it’s cool and breezy,” says Allison. At work, her mother Sonia harvests fresh herbs from the kitchen garden to use in the day’s lunch, which the students eat outside at benches in the shade of a tall redwood tree growing in the middle of the yard.

“I’m lucky and grateful that I can have my kids in that school, but it’s really expensive, and not all the people in this neighborhood have that opportunity,” Sonia says. “So I’m hoping we can have something like that, at least a quarter or half of that, here at International Community School. Because our kids need it.”

Julia Busiek
Julia Busiek is editorial content manager at The Trust for Public Land. She lives in Oakland, California.