Here we present the results of an investigation work oriented to study, within the learning process, the ability of conception, description and analysis that the superior level students show in front of some situations related with fluids physics that involve preconceptions (previous ideas) about some of these topics. This work intends to contribute with the reflexive practice of the teachers involved with the science comprehension and teaching, that is a fact that seems to be implicit in the debate of the conceptual construction and transformation.
Keywords: fluids mechanic, didactic, learn.