This contribution tackles the problem of the mathematical-didactic education of prospective early childhood education teachers, considered as an open problem. Relying on the anthropological theory of the didactic, we put forward a possible solution to this problem in terms of “study and research paths for teacher education” (SRP-TE). An SRP-TE is a new teacher education format based on the dialectic between formulating professional questions and building possible tentative answers, with teachers working in collaboration with researchers or educators. From the design and implementation of such an SRP-TE about natural numbers, we draw some conditions and constraints that affect their implementation in current university teacher education degrees. This kind of analysis is necessary to bring about effective changes in the education of prospective teachers.