This project is part of the Una Escuela Sustentable program by the NGO Tagma, which forms a network of sustainable public educational buildings across several Latin American countries.

Through an open call and a series of site visits, the school selected in Brazil was Escola Municipal Rural Nossa Senhora da Conceição, a public elementary school located in Mogi das Cruzes, São Paulo. Housed in a building from the 1950s, the school originally had only two classrooms, bathrooms whose sewage flowed directly into a nearby stream, and makeshift administration and teachers' offices in small, improvised spaces. At the same time, it had a vast grassy area and a beautiful surrounding landscape.

The renovation and expansion project was developed through a participatory process involving students, staff, and families. Each group engaged in tailored activities based on one central question: "What do you imagine for this school?"

The resulting program, shaped by the systematization of these activities, was guided by three main pillars: low environmental impact; construction as a hands-on theoretical-practical course; a 45-day construction schedule. As a result, the school’s covered area was expanded to include a new wood-frame classroom for first graders and a larger covered patio for use during rain or intense sun.

The former administrative office, located beneath the water tank, was repurposed to house two bathrooms (one accessible and one for staff). The gray water (from sinks and showers) is now treated in a banana circle, while the black water (from toilets), along with that from existing bathrooms and the kitchen, is directed to an ecological treatment system.

Attached to this area, also built with wood frame construction, are the teachers’ and administrative offices, topped with a green roof.

The multipurpose room—a space long desired by the children for music, dance, computer, and reading classes—is designed as a dodecahedron, creating an open and playful interior. Each radial wall of this polygon is made of rammed earth (taipa de pilão), supporting the wooden trusses of the roof, which are composed of small-section elements that are easy to handle. All twelve trusses meet at a central ring with a zenithal opening, reinforcing the room’s inviting and imaginative character.

The infill between the rammed earth walls is made up of built-in furniture, optimizing the structure’s form and doubling as playful elements: windows that also serve as doors, benches that face both inward and outward, connecting the space with the landscape.

This project brought together builders, the school community, public authorities, children, architects, students, and more—all working through an interdisciplinary and collective approach. The participatory design extended into the construction phase, with solutions emerging based on available resources. For example, furniture was made from leftover wood, and the wood frame insulation was filled with dried straw from a neighboring farm. These and other spontaneous, locally-sourced elements enriched the process and gave deeper meaning to the built space, resulting in architecture that truly responds to the real needs of the people and the place.