The School for Good and Evil, by Soman Chainani

Sophie always dreamed of being a princess in a story. In the small town of Gavaldon, two people are kidnapped every four years. One would turn out to be good, and the other would be evil. The children would be taken to the School for Good and Evil, to learn either to be a hero with an Everafter, or a villan with a Nevermore. These two were the highest honours awarded. This year, Sophie beleived she would be chosen for good, as she was pretty, and looked like a princess. Her best friend Agatha was the complete opposite, and everyone believed that she would go to evil. Sure enough, the school master came for them, to take than to their school. But then the tables turned. Agatha was dropped into the school for good, while Sophie into the school for evil. They both thought it was a mistake, and kept trying to swap places, but they gradually realized, they were in the right schools after all.