The Lycée Sainte-Geneviève is a private lycée, located in Versailles and providing preparatory classes for grandes écoles. It was founded by the Jesuits in Paris in April 1854. It is often nicknamed Ginette and sometimes BJ, standing for Boite à Jèzes.

The classes préparatoires aux grandes écoles (CPGE), commonly called classes prépas or prépas, are part of the French post-secondary education system. They consist of two years of study which act as an intensive preparatory course with the main goal of training students for enrolment in one of the grandes écoles. The workload is one of the highest in Europe(29 to 45 contact hours a week, with up to 10 hours of guided tutorials and oral exam sessions).