Eugène Train (1832–1903) was a French architect who taught for many years at the École des Arts Décoratifs. He is known as an advocate of rationalist architecture, which he applied with large schools such as the Lycée Chaptal and Lycée Voltaire.

The Lycée Chaptal, formerly the Collège Chaptal, is a large secondary school in the 8th arrondissement of Paris, named after Jean-Antoine Chaptal, with about 2,000 pupils. It was taken over by the City of Paris in 1848 after the founder ran into financial difficulties. The pupils were expected to go on to careers in commerce or manufacturing. The curriculum was innovative for its day, with emphasis on French rather than classical studies, and on modern languages and science. At the first it was primarily a boys' boarding school, but it is now a co-educational day school. The present buildings were completed in 1876. Notable alumni include Alfred Dreyfus, André Breton, Jean Anouilh, Daniel Hechter and Nicolas Sarkozy.