See Where Climate Science Conflict Has Invaded U.S. Classrooms

Conservative politicians are introducing bills that promote teaching climate science as controversial

So far, nine states have tried to pass laws that encourage a "teach the controversy" approach to climate change. KidStock/Blend Images/Corbis

Teaching high school students about climate used to be easier for Janelle Hopkins. She simply explained how climate differs from weather.

Then Hopkins began to wade into the controversies over climate change her students were hearing about on the nightly news. Her class now discusses whether recent rises in global temperatures should be blamed on human activity or natural cycles.

“I try to play devil’s advocate and argue for both sides,” says Hopkins, who teaches geoscience and AP environmental science at the Shadow Ridge High School in Las Vegas, Nevada.

Hopkins' approach is emblematic of a brewing conflict about how teachers across the country should teach climate change. Conservative legislators with a history of targeting evolution education have begun to take aim at climate science as well, encouraging educators to “teach the controversy” using some of the same tools and techniques that fuel continued support for intelligent design.

As seen in the interactive below, nine states have introduced multiple stand-alone bills that would grant teachers the authority to specifically present climate change as controversial, regardless of national science standards. Most of these measures have failed—for now. But two have passed, in Louisiana and Tennessee.

Meanwhile, critics worry that teachers who present the topic as an unresolved debate are doing a disservice to young minds.

“As a science teacher, she is teaching a mythology,” says Doug Lombardi, a science education researcher at Temple University who has been working with Hopkins. “There isn’t a climate change controversy, not from a scientific perspective.” Lombardi and Hopkins are instead working together to show both sides of the issue in a way that exposes students to the data and leads them to a scientific conclusion.

It's not just a matter of scientific accuracy—at stake may be the ability of future generations to deal with creeping temperatures, sea level rise and the other consequences of climate change.

Currently, most middle and high school science teachers do mention climate change in some capacity. These teachers typically dedicate between four and five hours of class time to the topic, according to a new survey conducted by the National Center for Science Education (NCSE), an advocacy group that supports teaching evolution and climate change.

“That’s more time than I would have guessed before the survey,” says NCSE programs and policy director Joshua Rosenau. “They’re putting in a reasonable amount of effort, especially middle school teachers.”

What students learn about the topic during that time varies from teacher to teacher. Some stick with the mainstream scientific view of climate change.

But more than 40 percent of teachers frame climate science as controversial. They tell students that some scientists believe natural forces could be the primary drivers behind the recent accelerated temperature changes.

That discrepancy mirrors a gap between scientists and the general public. Surveys of working climate scientists have shown that 97 to 98 percent of the most active climate researchers support humanity's greenhouse gas emissions as the primary driver of recent climate change. No major scientific organization, from the American Association for the Advancement of Science to the National Academy of Sciences, disputes this view.

Meanwhile, results from a Pew Research Center survey released in July show that only half of the public believes that climate change is mostly due to human activity.

Pew Research Center survey of U.S. adults Aug. 15-25, 2014. AAAS survey Sept. 11-Oct. 13, 2014. For exact question wording, refer to the topline questionnaire. Whites and blacks include only non-Hispanics; Hispanics are of any race.

“Teachers come from the communities they teach in and live in the communities they teach in,” says Rosenau. “They know where their communities stand.”

Beliefs about climate change tend to skew across political lines. Another recent Pew poll found that 71 percent of Democrats and left-leaning independents share the opinion of the scientific majority, as compared to 27 percent of Republicans and right-leaning independents.

In line with that ideological divide, conservative politicians across the country have begun attempts to weigh in on climate change education.

Last year Wyoming became the first state to reject the newly minted Next Generation Science Standards (NGSS), which were released in 2013 and have been adopted by 15 states so far. Citing mention of climate change, Republican state congressman Matt Teeters added a footnote to the state budget prohibiting spending on reviewing NGSS, as covered in the Casper Star Tribune. That footnote was subsequently overturned.

West Virginia’s state board of education approved NGSS, but only after tweaking the climate language, the Charleston Gazette reported. A first revision added emphasis to natural factors and temperature falls and questioned the credibility of climate computer models. After an outcry from teachers and climate advocacy groups, the board settled for replacing the phrase “rise in global temperature” with “change in global temperature.”

State congressman William Dunn, who sponsored Tennessee's successful 2013 "teach the controversy" bill, says its purpose was to help teachers confused about the subject. “We say that what they teach has to be backed by scientific evidence,” he says.

But to opponents of the bills, such language is a smokescreen. Dunn’s bill is similar—and in some places identical—to a template bill created by the Discovery Institute, a think tank that developed the tactic of teaching the controversy to promote teaching intelligent design alongside Darwinian evolution.

“The anti-science people are all running together and using the exact same strategies,” says Zack Kopplin. He was a high schooler in Louisiana when that state passed its bill, the first to lump climate change in with evolution as controversial. He became an activist and has been fighting the legislation.

So far, the legal battle to present climate change as controversial has had little impact on science textbooks, with the issue largely overshadowed by efforts to uncut Darwin.

“Evolution in our book is such a great big target that people almost overlook climate change,” says Ken Miller, a biologist at Brown University, who co-writes a popular high school biology textbook that includes a full page presenting a climate change case study. “Our editors asked us to be cautious about climate change, but we would never weaken the science,” he says.

However, Miller has had problems with non-science textbooks. A fifth-grade social studies book being developed by his publisher, Pearson, included language about climate change science that he says was too equivocal, using sentences such as “scientists disagree about what is causing climate change.” After contacting an editor, Miller received permission to rewrite the offending paragraph before the book came out.

Another social studies textbook for elementary school, by Pearson competitor McGraw-Hill, would have presented controversy and given equal voice to both sides. After posing the question, “Is global warming caused by human activity?” it presented one opinion from the Intergovernmental Panel on Climate Change—the world’s foremost scientific body on the subject—and an opinion from the Heartland Institute, a think tank that promotes skepticism about human-induced climate change. The publisher removed the pages before the book came out.

Louisiana teacher Steven Babcock brings in materials to supplement the textbooks he uses in his environmental science classes at the Louisiana State University Lab School, a public high school. The books he selects back the textbooks and the view that recent climate change is mostly caused by human activity.

But Babcock worries about other classrooms in his state, particularly those in rural schools like the one he attended growing up.

“Every classroom is a silo, with zero transparency,” says Babcock. “We have no idea what is being taught now.”

Editor's Note: This article has been updated to clarify the nature of the work being done by Hopkins and Lombardi.

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