Written by Dr. Joseph Cimpian, Associate Professor of Economics and Education Policy

Educators and policymakers often talk about the gender gap in science, technology, engineering, and math (STEM) during college, but the gender gap is not the same across all STEM fields. While many STEM majors have close to a 1-to-1 male-to-female ratio, physics, engineering, and computer science (PECS) consistently have some of the largest gender imbalances among U.S. college majors, with about 4 men to every 1 woman in the major. Using a large nationally representative dataset of almost 6,000 U.S. high school students followed for 7 years from the start of high school into their junior year of college, we looked at whether more men were going into these majors because of their higher math and science achievement.

In a new study published in Science, quite the contrary to considerably more men going into these PECS fields because of higher math and science achievement, we instead found that men with very low high-school GPAs in math and science and very low SAT math scores were choosing these math-intensive majors as often as women with much higher math and science achievement. In fact, when we ranked students by their high-school math and science achievement, men at the 1st percentile were majoring in PECS at the same rate as women at the 80th percentile. To put this in perspective, men at the 1st percentile had high-school STEM GPAs of about 1.5 (on a 4.0 scale) and math SAT scores of about 350 (on a 200-800 scale). In contrast, the women at the 80th percentile had high-school STEM GPAs around 3.5 and math SAT scores near 600. Despite the tremendous difference in these men’s and women’s demonstrated STEM competence, they were equally likely to major in PECS.

Why are so many low-achieving men choosing these majors while so many high-achieving women are choosing other majors? Previous research suggests that many student-level factors could contribute to the gender gap in PECS (and STEM more broadly), factors such as differences in confidence in STEM, women having a comparative advantage in English, women preferring majors that contribute to society, and gender differences in earlier career aspirations. Fortunately, the dataset we used for our analyses contained measures of each of these factors—along with many other factors—and we could test whether these factors explained the gender gap in PECS.

What we found was intriguing: All of the student-level factors previously identified by research collectively explained the gender gap among high-achieving students, but they explained very little of the gap among low-achieving students. In other words, the research field has done a very good job identifying ways that we might get high-achieving girls into PECS majors, but the field knows less about how to get average- and low-achieving girls into these fields.

One implication from this new work is the critical importance of assessing the gender balance in PECS involvement throughout the achievement distribution and thinking about this with respect to interventions. Our work suggests that prior research on how to get women into these PECS fields may work to attract high-achieving women. For example, interventions like coding camps for young women and fostering strong female peer networks may work to boost PECS interest and confidence and get high-achieving girls into PECS. That’s the good news. The bad news is that this work also suggests those same approaches are less likely to work for average and lower achieving women. Yet, average and low-achieving men are entering these fields, and those higher rates of entry are not explained by math and science achievement, confidence, prior interest, or many other factors. We have to ask what is it that draws lower-achieving men to these math-intensive fields because it’s not any of those other student factors.

A second implication concerns how educators and policymakers should think about evaluating progress toward gender equity. We found that women majoring in PECS were concentrated among high-achieving students, whereas men were more concentrated among low-achieving students. In the past (and still current practice) is to look at average differences and not look at how these concentrations may differ throughout the achievement distribution; but that practice can lead educators and administrators to have blind spots. For example, prior research suggests that the STEM pipeline has stopped “leaking” because there is roughly the same proportion of women in these fields in college and in graduate school, on average. Our new work suggests that is the wrong standard because women majoring in these fields in college are more concentrated among the highest achievers and men are more concentrated among the lowest achievers. Thus, if graduate schools select from the highest achievers, we should expect to see the proportion of women in PECS increase from undergraduate to graduate school, rather than stay the same.

All of this work suggests that, quite the contrary to needing to lower standards to improve gender equity in PECS, it is the women who are higher-performing in these majors. This new evidence that low-achieving men are majoring in PECS at higher rates than comparable women, combined with an emerging literature on the male-favoring cultures in PECS, suggests that efforts to dismantle barriers to women in these fields will likely attract high-achieving women and simultaneously discourage low-achieving men. Thus, working toward gender equity in these fields will likely raise standards, not lower them.