In this work we report a teaching intervention program with junior high-school students focusing on topics of the special theory of relativity is reported just after the discussion of usual kinematics. Starting from the analysis of common misconceptions, the enhancement of the conceptual profile of time was demonstrated through their identification of its relation with the reference frame. We describe the activities which are worked out. The analysis of classroom episodes and performance tests pointed out that the adopted methodology was profitable.
time; conceptual profile; modern physics in high school
