The Brewing Legal Battle Over Same-Sex Education Does separating boys and girls in the classroom help learning or reinforce dangerous stereotypes? Bob Wojcieszak / Charleston Daily Mail / AP From left: Angela Miller, Shaina Pack and Kayla Parsons are seen at East Bank Middle School in East Bank, W.Va, May 23, 2005. The school's students in grades six through eight are separated for classes in English, math, science and social studies. Other courses, including art, physical education and band, are mixed. Cohen is the author of Nothing to Fear: FDR's Inner Circle and the Hundred Days That Created Modern America The American Civil Liberties Union is on a vigorous campaign to integrate Mississippi's public schools, making requests across the state to find out which have segregated classrooms and weighing whether or not to sue. But the investigation isn't about racial segregation - it's about sex-segregation. Single-sex classrooms are a growing phenomenon across the country. In 2002, just about a dozen schools had them, but now as many as 500 do, according to the Associated Press. The movement shows no sign of slowing down and has set off a pair of debates: a pedagogical dispute over whether sex-segregation makes for better education, and a legal one - which the ACLU is at the center of - about whether this sort of separation violates civil rights laws. MORE: Can Parents Take Over Schools? Today's argument for sex-segregation increasingly turns on scientific - critics would say pseudo-scientific - arguments about how the two sexes acquire knowledge. The separation of boys and girls into different classrooms lets administrators and teachers tailor the instruction to what they see as the different learning styles of boys and girls. These "different learning styles," however, may be better described as gender stereotypes. Are you a girl who is interested in mathematics in its most theoretical form - the kind of math that predominates in university mathematics departments? Well, the National Association for Single Sex Public Education - a leading advocacy organization - does not seem to think that you exist. On its website, the group advises about teaching mathematics that "[w]ith boys you can stimulate their interest by focussing [sic] on the properties of numbers per se. With girls, you want to tie what you're teaching into the real world. Keep it real and relevant. For one lesson, it urges teaching boys by emphasizing the way the numbers work in the abstract - while girls should be told to bring in pineapples and pinecones to visualize the concepts. There are more stereotypes where that one came from - a lot more. MORE: Do Mothers Hamper Their Daughters in Math One way of knowing that the advocates are dealing in stereotypes rather than solid pedagogy: the science does not support what they are saying. Last fall, the journal Science published a wide-ranging study of the academic literature on same-sex education. The study acknowledged that there are sex differences in children's brains. But it debunked the idea that these differences have a significant impact on learning. While the Science piece did not find appreciable advantages to same-sex education, it did identify serious downsides. Separating students by sex, it said, "makes gender very salient," which "reinforces stereotypes and sexism." It has the same problems as segregation by race or income. "Any form of segregation undermines rather than promotes equality," the study said. MORE: Are Scout Handbooks Reinforcing Gender Stereotypes? But is same-sex public education illegal? It can be, if it relies on groundless preconceptions about the sexes that interfere with educational opportunities. For example, as the ACLU argues as part of their "Teach Kids, Not Stereotypes" campaign, it is unacceptable for taxpayer-funded schools to "teach boys to be active and aggressive - by shouting at them, spanking them, and allowing them to toss a football in class - while they simultaneously coddle girls, using soft voices, encouraging them to talk about their feelings, and giving them untimed tests to create a less stressful environment." Dividing up boys and girls and teaching them in this way is a rare form of bias. It is not simply discrimination against girls or discrimination against boys. It is discrimination against both. Cohen, the author of Nothing to Fear, teaches at Yale Law School.