The present article is guided to investigate for theoretical positions from the psychology and the pedagogy that refer to those “Mental Models”, specifically to those relating ones to the concept of “knowledge”. For such a purpose a journey begins for the cognitive theory of the psychology and later on pedagogic postures are recaptured as that of Johnson Laird. After clarifying mental model.s definition, it is looked for to relate it with the learning, and in turn with the teaching. During this search they seek to be answers regarding how it is known, and which an efficient way would be of teaching.