The existing school is an Open Air School (part of the school movement created to prevent the development of tuberculosis in children), and it was designed by Arch. Daners in 1942. It has 3 low volumes with hip roofs, these volumes are free standing in a landscaped green space, and they were used for common activities (dining, administration, etc.) because the classes were conducted in the outdoors. 
The school needs to double the built area, so the expansion inevitably has a strong presence. The landscaped ground is full of trees, so we designed a single, compact volume, to preserve as many trees as possible. Unlike the existing school, the expansion has 6 classrooms on 2 levels. We also wanted a different spatiality: a double-height integrates the two levels of classrooms.
From the outside we sought to hide the 2 levels with a solid volume (which is related to the existing school) and a continuous opening between that and the roof, which illuminates the second level. This determines that the classrooms are different, the ground floor classrooms have vertical windows, and the first floor classrooms have a continuous horizontal window. The roof has 3 sides instead of 4 (as the standard hip roofs), to integrate the double-height to the courtyard.