His is a report of the research on the strengthening of the argumentative ability, in fifth grade students of the Indalecio Penilla Educational Institution. We sought to strengthen the argumentative ability through a didactic intervention, approached from the fable as a topic and its analysis. The methodology used was qualitative-descriptive, type, case study. For the intervention, a didactic unit was designed, with five activities that presented argumentative situations based on some Aesop fables, which were applied to 32 students, of which 5 were selected for the qualitative analysis of the information collected and made through the application of diagnostic instrument, allowing to characterize the argumentative levels. This characterization showed progress, since in the application of the diagnostic instrument (Entrance), the majority of the students presented arguments that were structurally classified in level 1, in relation to the diagnostic instrument (Exit), the majority were classified in level 3. Since the fables deal with topics that are part of the daily life of the students, for that reason the creation of argumentative moments through this text, improved greatly after the didactic intervention, intentionally designed, allowing the construction of arguments with greater ease, in structure and functionality, strengthening in this way the argumentative ability of the students and demonstrating that an early teaching of the argumentation from the first grades of schooling, results in the formation of small argumentators in the classroom.