What it is not said about mass, volume and density in the Spanish students' books of Compulsory Secondary Education

This paper analyses the way in which the concepts of volume, mass and density are shown in the Spanish students' books for the second (LOMCE) and the third year (LOE) of Compulsory Secondary Education. The intention is to establish the presence or absence of elements in this resource, which can help us to eliminate, or to promote, the alternative conceptions associated with these concepts that students have. The results show that LOE text books present lack of several aspects related to these concepts, which don't improve substantially with the implementation of LOMCE. In general, students' books introduce density like a mathematical equation without previous qualitative explanation about its meaning. Moreover, they don't use to deal with alternative conceptions, like those related to the confusions between density and viscosity.