We designed a didactical proposal for teaching math through problem solving. This is aimed to guide teaching practices from the middle school institution Maria Josefa Escobar from Itagui, during the development of the variational thinking of the fifth to sixth grade transition. The methodology uses the case study of the problem solving’s role from the teacher perspective. This is followed by the design and implementation of a proposal based on a curricular, methodological and didactical component, and finally we socialized the appropriateness in the teaching practice. In conclusion, the interpretation of the teacher’s strategies and the class activity favors the design of complementary strategies, which allow the development of problem situations from the variational thinking