Book excerpt: When it passed Title IX of the Civil Rights Act in 1972, Congress seemed to be doing something laudable and also long overdue-prohibiting discrimination on the basis of sex in America's schools. But thirty years later, a law designed to guarantee equal opportunity has become the most explicit, government-enforced quota regime in America. Tilting the Playing Field is a trenchant insider's look at how one law--and its unintended consequences--has affected our view of sports, sex, and schools.