The study bears on a longitudinal research where one cohort of pupils has been followed up in ordinary classroom situations from the ultimate level of French nursery-school (5-6 years-old pupils) till the second level of French elementary school (7-8 years old pupils). When learning to read, pupil yet has at one’s disposal semiotic abilities related to both knowledge of the material objects and their uses, and of basic gestures and their meaning (what we globally call materiality). The present contribution will concentrate on the methodology used to highlight the materiality and its evolution throughout the three school-years.