A selection of oils, watercolors, crayons, prints, photographs and diverse materials from the collection of noted artist Francisco Díaz de León are published for the first time. The art collection comprises works by Federico Cantú, Antonio Balderas, Jean Charlot, Lázaro Belmont, Gonzalo Argüelles Bringas, Gabriel Fernández Ledesma, Agustín Lazo, Feliciano Peña, Tamiji Kitagawa, and other students that attended the Tlalpan open-space art school where artist and art collector Diaz de Leon was headmaster. The history of the creation of these schools begins in 1911, when the students of the Academy of San Carlos, the only higher education institution for art in Mexico; initiated a strike against the archaism, academicism and traditionalism of the teaching models. As a result, architect Antonio Rivas Mercado, the director of the school resigned in 1912. The new director Alfredo Ramos Martínez, an artist just arrived from Europe led to the introduction of new avant-garde teaching methods, based on his experiences in the old continent. One year later, in 1913 he founded the open space art schools, a learning alternative inspired in local themes and based on the Impressionism observation of nature. Although this school lasted only 3 decades open, its legacy is still strong: the teachers and students of these schools (EPAL) where later the main protagonists of the post-revolutionary and proletariat plastic movements, such as muralism, estridentismo, free art education and modern graphic art.