Should frames of reference be enacted in astronomy education? (Seminar)

Résumé En

The experiment that we present in this paper explores the teaching of Galilean motion principles observed in different reference frames, in an astronomical context. All grade 10 students in a French high school (the lycée Condorcet, Val de Marne) participated in two successive teaching-learning sessions, designed within the theoretical framework of embodied cognition. The learning material consisted of two versions of a spatiotemporal aspect map of the Solar System that allowed students to enact and observe trajectories from different points of view. The first was a printed, paper model (PO) that was used individually on a table. The other was a human version (HO). Thus, students enacted movements with either their fingers (PO) or their bodies (HO). Both sessions (HO or PO) used the same activities to illustrate the movements of Earth, Mars, and the Sun during a 24-h and 1-yr period, observed from different reference frames (terrestrial, geocentric, or heliocentric). Students’ conceptual understanding was tested using a questionnaire, which was administrated before and after each session, and three months later. The questionnaire described three situations in which the motion of an object is observed from two different points of view. We expected students to understand that speed and distance traveled were different in both cases. Our initial results suggest that the sessions did have a significant and lasting effect on students’ understanding of the dependence of motions on reference frames. While the degree of embodiment (HO or PO) does not seem to affect conceptual learning, the abstract operation of moving from one reference frame to another is facilitated when one has physically and repeatedly lived it.