In the framework of a subject of the Professorship in Physical Sciences (FCEYN, UBA), a didactic material entitled The pendulum of Foucault was produced. This theoretical - practica! work proposal is directed to teachers of the secondary level. This material puts in a explicit basis a didactic sequence for the classroom and the laboratory, based on the simulation of the historical experiment of Foucault (1851) and in the exploration of the previous ideas of the pupils about a non inertial reference system and the movements of the Earth. Such material was tested in an mini workshop on laboratory work (accomplished in the FCEYN in July of 1995), directed to secondary teachers in activity. The participantsof the workshop accomplished a very positive evaluation of the book.</p