Using data from the authors' 1998-99 survey of 1,040 eighth graders in Wuhan, China, this study explores the differences between single-girl and single-boy families with regard to parental expectation and investment in children's education, children's own educational aspirations, and mathematics performance. The authors found that contrary to the known intrafamily discrimination against girls common among families of pre-one-child generations and still common among contemporary rural families with more than one child, there are no gender differences related to education between single-girl and single-boy families in modern urban China. The authors found equally high educational aspirations and similar mathematical performance for male and female only children. They suggest that this gender equality in education is an unintended consequence of the one-child-per-family policy and that under China's current social and economic conditions, girls are better off living in one-child families in the big cities of modern China.