18.  Barnard College

Barnard admits only women, but it has a partnership with neighboring Columbia University, an Ivy League school in New York City. The annual price of attendance is $69,912, but only 50 percent of undergraduates pay the full amount. Families earning $30,000 or less pay an average of $6,225, and those earning $30,001 to $48,000 pay $6,207.