When the Île-de-France region, the owner of the high school, launched a competition for the expansion of the Édouard-Branly school complex, which had become too cramped, it did not contemplate anything other than a roof-top extension on the existing building. According to Jean-François Schmit, this type of development would have disfigured the elegant brick architecture typical of the high schools built in the so-called “red” suburbs in the 1930s. The grade of the site would have made the “graft” too pervading, as it would have been highly visible in the upper part of the plot where, because of the slope, the school is only single-floor. In addition, there was doubt as to the flat roof’s ability to support new floors and to accept an increase in its service load. At the risk of being excluded from the bid process, Jean-François Schmit decided to focus on the empty spaces rather than the built area, proposing the restructuring of the existing playgrounds which, by exploiting the differences in level and the slopes, made it possible to find the requisite surface area while enabling better connection between the 1930s building and its annex, built in the 1970s.
This work on the empty spaces began with the restoration to the pupils of the courtyard between the original building and the extension. The boiler room, which occupied more than half of that space, was transferred to a new basement, while the existing ground was extensively excavated to bring daylight to spaces at the foot of the building that have, in fact, been able to obtain an influx of natural light. This arrangement also made it possible to differentiate two places: an upper, busier playground and a lower, quieter, playground. An underground corridor connects the two buildings across the main playground; it is illuminated by light sources incorporated into benches. A lightweight but broad glass canopy duplicates this circulation, providing a covered outside route. The decision to build beneath the playground freed up a third space, that of the flat roof of the 1930s building that, fully paved, can accommodate the pupils but so far remains unused. Jean-François Schmit also modified the extension built in the 1970s. The creation of a capping and of a base, the exploitation of vertical connections enabled the linking of this massive and anonymous building to the rest of the school complex.