A primary school wishes to open kindergarten classes and take the opportunity to rethink the organization of the existing building. The restructuring/extension project stands out with a decidedly sustainable architectural approach, featuring a CLT panel structure and the use of bio-sourced materials for the thermal renovation of existing buildings. For the implementation of the extensions, we propose a layout that closes off the last side of the courtyard to accommodate the two missing classes, while the cafeteria is expanded opposite; a decimation of the courtyard accompanies the project. The two new kindergarten classes thus adopt a through design that promotes natural ventilation, ensuring a healthy and comfortable environment for the students. The thermal renovation of the existing structure focuses on energy efficiency with the use of bio-sourced materials (hemp natural fiber insulation). An interior restructuring also allows for reconsideration of acoustics and summer thermal comfort in the classrooms for the children’s well-being.