ÀÏ°ÄÃÅ¿ª½±½á¹û

It should be a foregone conclusion that treating boys and girls differently in school is sex discrimination. Except in many schools across the country that isn't the case. Hopefully that's about to change.

A issued Monday by the Department of Education makes clear that single-sex education programs based on sex stereotypes are unlawful, as is the practice of employing different teaching methods for boys and girls. Specifically, the department clarified that the justification for sex separation of students "may ‘not rely on overbroad generalizations about the different talents, capacities, or preferences of' either sex," and emphasized that "likewise, the evidence cited in the justification may not rely on these overly broad generalizations."

This is critical because almost all of the educational programs that the ÀÏ°ÄÃÅ¿ª½±½á¹û reviewed as part of its "Teach Kids, Not Stereotypes" campaign, which investigated the use of single-sex classrooms in public schools across the country, relied on precisely such generalizations. Indeed, the presumption that boys and girls are "hard wired" to learn differently was incorporated into every aspect of these programs' structure, from curricula to teaching methods to classroom activities and décor.

If you are wondering what this looks like on the ground, here are some examples of what our investigation found.

In the Hillsborough School District in Florida, all kindergarten teachers in single-sex classrooms were required to attend a training entitled "Busy Boys, Little Ladies." The school district encouraged teachers in boys' classrooms to "be louder" and "have high expectations," while teachers in girls' classrooms were expected to be "calmer" and "less critical." In one instance, boys had an electronics day, where they could bring in all their electronics and play them if they behaved, while girls did not. In another, the teacher in a girls' classroom gave each girl a dab of perfume on her wrist for doing a task correctly.

In Middleton School District in Idaho, boys were seated shoulder-to-shoulder while girls were seated face-to-face on the theory that girls are more cooperative while boys are more competitive and should not be forced to make eye contact. The program called for "large amounts of explanation for assignments" for girls and "limited teacher explanation" for boys. Boys were permitted to play and exercise while girls were required to maintain a "quiet environment."

And a personal favorite of mine: Teacher training materials used widely across the state of Florida, including in Broward, Hernando and Volusia counties, advised teachers to "reassure" young female students struggling with math that "when her brain is ready she'll be ready."

These examples show the harms of making crude judgments about what is best for kids based on their sex. No one denies that there are biological differences between boys and girls. But these have simply never been shown to translate into a need to teach boys and girls differently. And we all know kids who don't conform to sex stereotypes – including, .

The Department's clarification should establish once and for all that programs based on this model violate Title IX. It also contains other important safeguards, including requiring schools to justify each single-sex classroom separately by grade and subject (rather than implementing sex segregation across an entire grade or school), clarifying that affirmative consent is required for participation, establishing that transgender students and students with disabilities must be given equal opportunities to participate in single-sex classes (including by honoring students' individualized educational plans and ensuring that students are permitted to participate in the class that conforms to their gender identity), and emphasizing the programs must be evaluated to ensure that they are meeting their objectives and not perpetuating sex stereotypes.

We look forward to disseminating the Education Department's guidance widely to educators and policy makers. Hopefully it will provide a much needed course-correction and help put a stop to this costly, misguided, and discriminatory experiment with our kids.

Learn more about single-sex education and other civil liberty issues: Sign up for breaking news alerts, , and .