This chapter analyzes how the International Bureau of Education (IBE, Geneva, Switzerland) approached educational equality between the two world wars, focusing on special classes and rural schools. It shows that the IBE promoted the idea of universal access based on differentiated methods rather than standardized teaching. Rural schools are presented as possible sites for pedagogical experimentation, partly due to their link with local environments. Special classes are examined as one way to address student diversity, rather than only as instruments of exclusion. Using archival sources, the study describes this differentialist position. It highlights an understanding of inclusion grounded in contextual adaptation instead of uniform educational models.