Last week, researchers at the University of Colorado published a psych experiment that seems almost too good to be true. They showed that two 15-minute writing exercises, administered to an intro physics class early in the semester, could substantially boost the scores of female students. Even more curious: the exercises had nothing to do with physics. Instead, students were asked to write about things that mattered to them, like creativity or relationships with family and friends. How could a few paragraphs on personal values translate into enduring better mastery of pulleys and frictionless planes?

When it comes to math and science classes, women can be subtly hampered by negative stereotypes about their gender. This is the idea of stereotype threat, advanced by psychologists Joshua Aronson and Claude Steele, and now solidly established, as I’ve written in Slate before. Stereotype threat can roar into action when members of any stereotyped group are primed to think about belonging to it—in other words, when women focus on being female or African-Americans on being black. It causes performance problems, but stereotype threat can also be countered, often in simple ways. As the Colorado writing exercises show, getting women to focus on things they care about can buck them up. The lesson is that small doses of affirmation can do a lot of good.

Here’s what we know about how stereotype threat works: In the 1990s, researchers found that women taking a math exam who were told that the test had “shown gender differences in the past” scored lower than other women with equivalent math backgrounds. Similarly, women asked to watch commercials in which ditzy ladies gushed about brownie mix afterward expressed less interest in quantitative pursuits. Stereotype threat is a universal offender: It can sabotage white men on the basketball court or men more broadly on a test of social sensitivity. Whenever people are made to worry that they might confirm a negative assumption—for instance, that girls can’t do math or that white men can’t jump—they may be less likely to do their best. Frustratingly, the stereotypes they want so badly to avoid instead may instead become self-fulfilling. For women on a math-and-science track, the threat is likely to worsen the further along they get, both because they will have fewer female classmates and role models, and because they may have stronger “math-equals-males implicit associations,” as psychologist Cordelia Fine points out in her terrific new book, Delusions of Gender.

At the same time, in 2007, psychologists handily proved that stereotype threat isn’t intractable with a study of top-tier calculus students at the University of Texas. At the beginning of one exam, half the students read a statement that said, in part: “Analysis of thousands of students test results has shown that males and females perform equally well on this test.” The women who read this statement scored significantly higher on average than other women in the class. They also scored higher on average than the men.

Now, the Colorado researchers have shown that writing exercises can also make a difference for female science students. In a double-blind study published last week in Science, the researchers worked with 399 undergrads in a calculus-based physics class. They randomly assigned some of them to write about two or three items from a list that included “learning and gaining knowledge,” “belonging to a social group,” “athletic ability,” “relationships with family and friends,” and “sense of humor.” They were then told to reflect on why these things mattered to them. (The other students received the same list of values, but were asked to choose the ones least important to them and write about why they might be important to other people.) Students completed these exercises early in the semester, at moments when they might be expected to feel uncertain about the class: the first week of school and then the week before the first midterm.

The benefits were dramatic. Most of the women who received C’s in the class were in the group that had written on values they cared about least. Most of the women who received B’s had written on what they cared about most. (There was no effect for women who were getting A’s, or for men in general.)Women who affirmed their own values also scored higher on a standardized exam of key physics concepts, taken at the end of the term. Strikingly, women who’d said they believed the stereotype that men are better at physics were the ones who benefited from the exercises the most.

How did all of this work? Psychologists Akira Miyake and Tiffany Ito and physicist Noah Finkelstein, who were among the study authors, said they didn’t know for sure. But they speculated that the women who wrote about things they cared about early in the course felt slightly more comfortable or relaxed in class. Maybe this helped them to absorb more material or motivated them to work harder. And maybe that in turn meant they did slightly better on the first exam, which in turn boosted their confidence and motivated them even more. It’s easy to imagine such a virtuous cycle.

The current study followed physics students for one semester. But it’s possible the effects of this sort of writing exercise could be longer-lasting. In a 2006 paper in Science, Stanford * psychologist Geoffrey Cohen showed that similar writing tasks boosted the grades of African American middle-school students. Two years later, after several follow-up exercises, the benefits were still apparent.

Of course, stereotype threat isn’t the only reason that women remain underrepresented in math and science. Previously, some of the co-authors of the new study found that differences in background explained 60 percent of the disparity between their male and female students’ physics scores, with the men more likely to have taken physics in high school. After giving the affirming writing exercises, the researchers did another analysis that controlled for differences in prior math scores, which correlated with who’d done more or less past math and physics coursework. This time, they found no statistically significant gender disparities in the scores for the standardized physics test or other physics exams. The implication is that if women had the same background in science as men, on some measures, writing exercises like this one might close the rest of the gender gap—or at least come close. In a world where women may worry that they’re not as good at science, it looks as if we have an easy-to-use tool for helping them zap their self-defeating demons.

Correction, Nov. 29, 2010: This article originally stated that psychologist Geoffrey Cohen was based at the University of Colorado. He has moved to Stanford. (Return to the corrected sentence.)

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