Where does Blair attend school in the book, All I Want Is Everything: A Gossip Girl Novel?

The Constance Billiard School for Girls is the expensive private school where Blair and her friends go, both to obtain their education and pursue their social lives, which in many cases seems to be as much of a priority (and for Serena, even MORE of one). Vanessa also attends this school, but feels extremely uncomfortable there with the other, more "upper class" girls.