In a classroom in Dallas, Texas, a teacher tells her students that climate change is a natural phenomenon. Meanwhile her counterpart in Queens, New York, presents evidence to the contrary. Both are providing teenagers with a lens through which they'll interpret environmental policy as they reach voting age.
Across the country, high school teachers have their own environmental science curricula. They're all expected to educate students about hot-button issues, but their approaches may differ based on where they live. Science might seem like a set of inflexible laws of nature, but in practice, its test tubes and titrators leave room for gray areas — especially when politics come into play.
"It's not at all surprising that you would be able to see variation between states, and have their opinions be reflective of the political context," said Priscilla Wohlstetter, a research professor in education policy and social analysis at Teachers College in New York.
Forty-two states, including New York, adhere to the set of academic standards called the Common Core, while Texas is among the eight that do not. Even if a state does use the national guidelines, it can put its own stamp on them — 15 percent of standards in the Common Core are tailored to particular states, Wohlstetter said.
In practice, this can mean that states that are more environmentally conscious, like those in the Pacific Northwest, might prioritize the subject in their personalized sets of rules, she added.
Amra Sabic-El-Rayess, an assistant research professor at Teachers College, told NBC that politics also have a stake in education because "the most conspicuous goal of the political and economic elites in any society is to retain their dominion over masses." In the United States, she has noticed how "many forces have and will continue to infiltrate curricula wherever and however possible," a trend she said will only expand as the country becomes more ideologically polarized.
Global warming may be the most vivid example of how a syllabus can reflect local politics.
The scientific consensus holds that climate change is harmfully accelerated by an increase in greenhouse gases produced by human activity, and that's accepted by most Democratic politicians. But many Republicans disagree.
Republican Scott Pruitt, the administrator of the Environmental Protection Agency, contradicted his own agency's position on greenhouse gases when asked about how human activity affects the climate in a March interview. "I would not agree that it's a primary contributor to the global warming that we see," he said.
When journalists brought up the quote at a White House briefing, press secretary Sean Spicer defended Pruitt, saying that “that’s a snippet of what Administrator Pruitt said. He went on and said I don’t think we know conclusively, this is what we know."
Because of disagreements in the national dialogue, many of which are driven by industrial interests, there's room in class for students to debate global warming's causes.
"I teach climate change as a natural phenomenon, because I teach the different extinctions and the different history of our planet from emergence to now, and if you do that, you will see that we've had several ice ages," said Theresa Oriabure at Hillcrest High School in Dallas.
But she added that "even when you have a natural phenomenon, that natural phenomenon can become a problem when you enhance or overdo it, which is what we've done with climate change."
At Townsend Harris High School in Queens, Shi-Bing Shen also looks at the ice age cycles, and her students contemplate whether recent temperature changes should cause concern by examining whether these fluctuations follow the patterns of the past.
Her class watches Al Gore's 2006 documentary, "An Inconvenient Truth," and considers what's real or exaggerated in the film. And they study the release of carbon monoxide, which, according to Shen, is obviously a problem created by industry.
"A lot of the kids in class do believe that climate change is man-made," she said. "That's based on evidence that we have."
Energy is another topic where regional politics may ooze into the classroom. Both Shen and Oriabure take a critical view of traditional energy, but they diverge when it comes to alternative sources.
"Given the relevance of the oil and gas industry in Texas, it is not surprising that politics will always attempt to influence the state's environmental science curriculum," noted Sabic-El-Rayess.
In New York, Shen has her students debate fossil fuels and nuclear energy. Classmates take on roles as concerned citizens and environmentalists to voice opinions on possible downsides of each, discussing deterrents like the nuclear fallout from the Fukushima disaster and air pollution from burning coal.
When Oriabure covers energy in oil- and wind farm-richTexas, she focuses on the distinction between renewable and nonrenewable resources. Her students explore which regions of the world have an abundance of each type of fuel and go over the extraction process so they're aware of the damage done.
"It was a big thing for them, when they heard [then-presidential candidate Donald] Trump say that he was going to put the coal workers back to work," she said. They understand the need for gainful employment, she added, but they're concerned about the impact more coal mining could have on the environment.
This year, Oriabure didn't do much on alternative energy sources. Meanwhile, Shen investigated the pros and cons and practical applications of solar, wind, hydroelectric, biofuel and geothermal energies. For a local connection, her students calculated how much it would cost to cover an entire house in New York with solar panels.
Oriabure hopes to get funding for windmill- and dam-making kits to show kids how both methods work, and to delve deeper into greener fuels next academic year. Her focuses make sense regionally: wind energy is popular in Texas, as is hydroelectric power. In New York, Shen makes sure to note downsides to hydro as well as upsides, teaching her students that dams can block salmon migration or desecrate sacred lands.
Fracking, a topic that's been controversial in the past, has faced more criticism even in Oriabure's Texas classroom as evidence mounts that it negatively affects the environment.
Unlike in New York state, where fracking is banned, Texas has a huge fracking industry that has provided over 100,000 jobs in North Texas alone, according to a 2016 study by North Texans for Natural Gas. Oriabure said that her students have become skeptical of fracking companies since their communities have experienced more frequent and severe earthquakes as the practice has expanded.
But she tries "not to prejudice my presentation in any way," she said. "We talk about the pros and cons, because there are very positive things about fracking."
Shen shows her students a fracking video and educates them on how the technique can contaminate groundwater, a conclusion drawn by the EPA in December, with some caveats. She displays a diagram of the fracking process, and her students share their thoughts on an article about the technique.
"They're almost at the voting age," Shen said. "They need to know what's real."
Like Oriabure, she doesn't try to sway their beliefs, she said, but presents them with the information she thinks will help them make an educated decision.
Where both teachers seem to converge is in their emphasis on water contamination, a subject that's now buzzing nationally.
Oriabure bought her students kits so they could test all of the water fountains and sinks at Hillcrest, which is housed in a building with pipes from the 1950s. They're set to present their findings to the school board in the next few weeks, to supplement similar investigations by public officials that the teenagers considered too superficial.
During spring break, Shen asked students of hers who were traveling to bring back a water sample for testing.
These experiments come on the heels of recent studies that indicate millions of Americans may be drinking unsafe water because of lead contamination. Despite concerns over possible Flint-level crises around the country, President Trump rolled back Obama-era reforms curtailing water pollution with a directive in February.
"If you're teaching environmental science, you have to be current," Oriabure said.
She requires her students to watch the news and stay up on environmental policy. Shen also asks kids to tune in — whenever there's a major political event, they choose relevant stories to discuss.
"I've taught them how to read an article with lots of grains of salt," she said.
Though Shen described herself as a tree hugger, she doesn't expect all of her kids to adopt her views. She appreciates that environmental science is never black or white and raises complicated ethical questions. If a farmer in Brazil practices slash-and-burn agriculture so he can feed his family, she asked, is he really evil?
But while Shen does add nuance to her subject, she also tries to teach teenagers practical ways to be responsible by recycling, or by using a cup instead of running the tap while they brush their teeth.
"It's not about winning or losing," she said. "It's about how to coexist."