In the sixth-grade class, the boys are making robots, more than a dozen students stand around work stations and chat as they cut cardboard with scissors, or glance at comic books for inspiration.
In another classroom down the hall, girls are working, quietly and independently, on the same project.
The recent scenes at Atlanta's Martin Luther King, Jr. Middle School may become more common in the coming years as a change in federal regulations is expected to make it easier for public schools to experiment with single-gender schools and classrooms.
Supporters argue boys and girls learn differently, and that single-sex education can help both genders perform better. Critics compare it to the "separate but equal" segregation-era classrooms.
At least 223 public schools across the country already offer some single-sex classrooms, up from four in 1998, said Leonard Sax, director of the National Association for Single Sex Public Education.
Sax predicts thousands more schools will join the movement once the Education Department finalizes new Title IX regulations first proposed in March 2004. Department officials have said their final regulations should be released this summer. Sax said he expects them this month.
Backers of single-sex classes point to research that shows the genders learn in different ways. At elementary school age, they say, girls' vision and thought processes have developed to respond better to color and detail, while boys' brains are more apt at processing motion and direction.
"If you don't understand those differences and you teach boys and girls as if they were the same, the end result is a kindergarten classroom where the boys tell you drawing is for girls and a middle school classroom where girls tell you computers are for boys," said Sax, one of the nation's leading proponents of single-sex education. "If you don't understand gender differences, you end up furthering gender stereotypes."
Not everyone agrees. A 2004 statement from the American Association of University Women says single-sex classrooms distract from real problems in schools and "would throw out the most basic legal standards prohibiting sex discrimination in education," reports AP.
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