C.f.E = Classroom for Emergencies. This project responds with architecture to the problems established by nature, principally for the hottest areas in the north of Argentina. It is a classroom specifically focused in its use as a tempory replacement for any e ducational building which has been damaged by any natural hazard, or any extreme emergencies. Because of such a specific circumstance, there were various unusual requirements, which are the following: A space big enough to shelter 30 students; to be used from 10am to 4pm; to be economically sustainable; easy to assemble when needed; easy to transport through earth and water; easy to produce in big amounts when needed; respond with architecture and not infrastructure to the problems imposed by the weather/nature. The language that the C.f.E uses to respond to the demands explained above come from the action of folding, as in origami. This is present from the moment it is transported, dismounted, and unfolded to form the space containing the students. For example, the door is not understood as a perforation in a wall, but as a plane that folds and opens a space where students and teacher can pass through. Another example is when the whole east façade folds down to expand the surface of the classroom so, if needed, more students can be sheltered. Additionally, if there are more children than expected, the equipment of the classroom, such as chairs, can be folded and used as shelves so they do not obstruct the development of a normal lesson.