We present quantitative results for the doctoral thesis of the first-named author of this article. The objective was to recommend and test a teaching proposal for core knowledge of evolutionary biology in secondary education. The focus of the study is "Problem cores in teaching". The "Weaving evolutionary thinking" teaching unit, designed for and tested in this study, entailed: selecting basic evolutionary knowledge from the model of evolution through variation and natural selection; designing a coordinated set of activities, teaching resources and evaluation tools; leading a process of teacher training; and building bridges between: the teaching model, research into the teaching of evolutionary biology, our own teaching experience and that of the secondary school teacher who participated in the project. The data collected through questionnaires show significant differences in favour of the experimental group, which means that the proposal may be favourably assessed in the context of Mexican education, in terms of feasibility, relevance and the pedagogical transformation of knowledge.