Late to the party.....
St DS8's school 6-12th, the classes are gender separated in 7th and 8th. When they first did this there was an uproar, but grades and test scores have proven that it works.

The thinking is that the girls don't want to be too smart around the boys and tend to dumb down. The boys, hormones raging aren't capable of coherent thoughts with girls in the room....LOL!

They still meet up in the halls between classes and at lunch, so they do get some time together.

Shari
Mom to DS 10, DS 11, DS 13
Ability doesn't make us, Choices do!