Single-sex public education.

• Position: TRENDS AND TRANSITIONS

Did you know that the optimal classroom temperature for learning is 68 degrees for boys, but 74 degrees for girls? And that for every 100 girls who repeat kindergarten, 194 boys do. These are just two of the reasons single-sex education is becoming fashionable again.

In recognition of social, physiological and learning differences between boys and girls, single-sex education divides boys and girls into separate classes or different facilities in hopes of raising academic achievement. Some even see single-sex education as one solution to closing the achievement gap of minority students.

Supporters point to studies that demonstrate learning differences between girls and boys. One study observed several high school geometry classes to understand why there are so few women in the field of mathematics. The researchers found that males were asked more questions in class, and teachers interacted more with males than with females. Other researchers have found that teachers of single-sex classes have reported better achievement from boys when they are allowed to stand up, sit on the floor, or walk around during class.

But not everyone agrees this is the way to go. Opponents call single-sex education "sex-segregated" education and argue that many of the studies...