Learning by Teaching Goes Global: Evidence, Networks, Methodological Limits, and Plausible Reach of Jean-Pol Martin's LdL Concept

This working paper examines the international dissemination of Jean-Pol Martin’s concept Lernen durch Lehren (LdL), known in English as Learning by Teaching. Based on a structured overview of bibliometric indicators, historical network data, teacher-training contexts, school-program references, and international evidence from Europe, Asia, and North Africa, the paper shows that LdL has developed beyond its German origin into a decentralized and internationally visible educational concept. The article distinguishes carefully between documented evidence, plausible assumptions, and areas that remain unverifiable. A central part of the paper is a transparent model-based estimate of the possible annual reach of LdL worldwide. Since no central statistical database exists, the estimate is not presented as a measured figure, but as a cautious reconstruction based on available reference data. The paper also situates LdL within the broader Zenodo series on Jean-Pol Martin’s semantic field, algorithmic visibility, human-AI collaboration, and participatory education. Its specific contribution is empirical and infrastructural: it documents that LdL is not only a coherent pedagogical theory, but also a long-lasting, internationally traceable and institutionally connected educational practice.