The resolution of mathematical problems is considered by the MEN (2006), as the axis central to the teaching of mathematics, hence the importance of promoting and promoting from the school, the necessary skills to do so. In this sense, the project "The resolution of mathematical problems, through the implementation of a unit Constructivist didactics, based on the development of mathematical competences in fifth grade students of basic education. ", uses the participant observation of students, from their academic reports in the area of mathematics and take the results of the Test Saber (2016) and Aprendamos (2017), analyzing them from three categories: communication, reasoning and resolution; where the difficulty that the students solving mathematical problems