The project consisted in the expansion of the "Jesús de Belén" kindergarten, which belongs to the NGO of Fraternal Aid San Pablo. Annually, this building receives more than 90 children in social risk from a vulnerable neighbourhood named “Los Héroes de la Concepción”, in Recoleta, Santiago. The extension provided a multipurpose room and an office for the kindergarten’s Director. Both volumes were built together, to optimize resources. The design of the project and its building process were scheduled almost together, which allowed adjusting to a very low budget. Considering that the courtyard of the kindergarten is the only space available for the large events and ceremonies at the end of the year, the multipurpose room was designed as ‘a stage’, thus located to be opened to the courtyard. This idea was supported by the use of a mobile enclosure that can be opened or be closed according to the courtyard’s use.