Zurich suffers from an extreme shortage of school places. The canton reacts to this problem with temporary buildings. Two recently completed projects illustrate different approaches. On the site of a former freight railway station Pool Architekten together with Baubüro in situ have built a demountable modular building for 650 pupils. In contrast on Irchel university campus, Stücheli Architekten have made spaces for 2 200 schoolchildren in existing building shells in which, over the next three years, three canton schools will find a temporary home. Provisional school space tests the possibilities of building rapidly, efficiently and simply. While at Irchel high spatial density reaches its limits, the “new roughness” of the modular building method at the freight train station allows a greater degree of appropriation and the establishment of an individual identity in a location as yet unfinished.