Paper interfaces are an alternative for controlling a computer. Typically, users interact with pieces of paper which are detected by a camera and augmented with relevant information by a projector. The development of paper interfaces, historically, aimed at merging digital and physical versions of documents, enabling to transparently work on one or the other. Furthermore, in the new era of natural interaction techniques, the special affordances of paper can be of great value as a basis for tangible interaction and Augmented Reality: digital objects, linked to paper artefacts, can be manipulated by folding, cutting, orienting, etc. In the context of classroom technologies, paper interfaces are especially appropriated, because paper is integrated and ubiquitous in the school environment and learning processes. Students and teachers are familiar with its properties and know how to interact with it. The goal of this dissertation is to explore the possibilities of using paper as a support for the learning content and more importantly as a tangible body. We focus on geometry education at primary school, because it is a domain where these two aspects of paper can be extensively exploited: pupils can write formulas or draw figures, and they can also move cardboard shapes, or fold along symmetry axes. We designed five series of pedagogical activities: classifying quadrilaterals, mastering the protractor, communicating angles, exploring symmetries, and describing physical transformations with geometrical concepts. These activities are experimented in increasingly valid settings, such that the last series took place in regular classrooms. We also developed methods to analyse the learning activity happening during these experimentations. Our studies revealed important insights on paper interfaces and their application in classroom education. The variety of collaborative scripts that could be created shows the flexibility of paper as a material for building user interfaces that support pedagogical designs. Such flexibility can be further exploited to enable teachers to create their own pedagogical Augmented Reality applications. We also observed many examples of uses that were not intended in the original design, which we refer to as “creative appropriation”. As a result, our paper interfaces were integrated in the everyday conditions of the classroom, used intuitively by the pupils, and managed autonomously by the teachers.