While Harvard president Larry Summers provoked a fury last year by raising the specter of differences in cognitive ability between men and women, another recent study from the National Bureau of Economic Research examines the measurable differences in performance between boys and girls. Researcher Thomas Dee examines the marked achievement gaps between girls and boys in reading, science and mathematics in light of their teachers' gender.

Thomas Dee found that "assignment to a same-gender teacher significantly improves the achievement of both girls and boys as well as teacher perceptions of student performance and student engagement with the teacher's subject." While boys tend to fall behind girls' test scores in reading, Dee found that just one year with a male English teacher would eliminate nearly a third of the reading gap among 13-year-olds, by improving the performance of boys--and simultaneously harming that of girls.

Similarly, boys are more likely to not look forward to a particular academic subject when the subject is taught by a female, and are also more likely to be seen as disruptive when assigned to a female teacher. Girls, on the other hand, are more likely to claim that science is not useful for their future when taught by a male, and their science scores reflect their lack of investment in the subject.

In other words, gender gaps in educational outcomes may depend largely on the gender distribution of teachers by subject. Just a few years ago, Dee surprised the research community with his study of the impact of teacher race on student achievement, producing the first serious scholarship suggesting that teacher-student racial matches are in fact beneficial.