Resumen

This study analyzes the teaching of the topic of money in mathematics by a fifth-grade teacher. The research is naturalistic-descriptive and is based on a case study with non-participant observation. Indicators of didactical suitability of the onto-semiotic approach were used (ecological, mediational and cognitive suitability) were used in this analysis. With respect to ecological suitability, the context used by the teacher was related to the daily experiences of her students and she was aware of many aspects of the curriculum. Regarding mediational suitability, the teacher used a variety of technological and manipulative resources. Finally, in the case of cognitive suitability in the development of the various activities, students’ previous knowledge and their individual differences were taken into account.