At the time, more than 30,000 children were without a school and 65.7 percent of the population was illiterate. During the Vasconcelos era (1921-23), new schools had been built under the direction of architect Carlos Obregón Santacilia: the Centro Escolar Benito Juárez, Centro Escolar Belisario Domínguez, la Escuela Gabriela Mistral in honor of the Chilean poet who was then participating in the Mexican literacy campaigns and the Escuela Malinalxóchitl, among others. The problem was that such schools were very costly, both due to the required materials and the decoration of the premises. The national population was 16,600,000, inhabitants, approximately, 40 percent of which was school-aged (between 5 and 24 years old).The functionalist schools were seen as the solution because they were based on the desire to conserve funds and to construct buildings according to the priorities of the moment, without forgetting the needs of childhood. The functionalist idea proposed by Juan O’Gorman (1905-82) can be summarized with the following phrase: “La forma sigue a la función” [Form follows function]. Beginning in the 19th century, new elements for construction—glass, reinforced concrete, and steel—had begun to transform architecture and turned engineering into a very specialized field. Ornamentation was overshadowed by what was useful, necessary and required by an industrial society that was in a process of transformation. Factories, banks, industries and schools nourished the urban landscape. Utility had to go hand in hand with economy; ornaments that made a project more costly and that delayed its completion had to be eliminated. Architects had to submit proposals in line with the motto “architecture or revolution,” and they had to be attuned to the changing times.