For Quadir Askew, having girls in his sixth-grade class at Hawthorne Avenue School in Newark was just "drama" all the time. "Now it's real easy to concentrate with all boys," said the 12-year-old. "We don't have a lot of distractions and we get good grades." Hawthorne is one of only a handful of schools in New Jersey to have same-sex classes. Though prohibited by state and federal sex discrimination laws, a provision in the federal No Child Left Behind act gives public schools the flexibility to implement such programs as they try to improve academic performance. "We were failing and...