The subject of the present work consists of the application of a didactic proposal of learning by discovery in a constructivist context about the multiplication tables, with the aim of exploring and describing the way in which the student approaches and develops knowledge about the multiplication tables, and at the same time to find out if the strategy provides a better learning opportunity than the one traditionally used by teachers. A learning proposal was constructed for its application and its results were measured by means of a post-test, the filming of videos and the analysis of the comments and solutions to problems generated by the students. The research sample consisted of 28 students from the second grade group, section "B". The results of the pilot test (2008-2009) are presented, as well as those of the application group and subsequent research (2010-2011) carried out based on the interest of the data obtained.