A longitudinal approach to the appropriation of Science Ideas: an emerging Cognitive Model

A research approach, active since three decades, is sketchy described. Its aim is to clarify, starting from the phenomenology of explaining-understanding interactions followed along years within groups of students, two mutually correlated theoretical and practical nodes: i) how to restructure the discipline presentation (e.g. basic physics and math) to be longitudinally resonant with students' gradual appropriation, in both understanding and motivation; ii) how to infer a cognitive model able to account for success (insuccess) in the school active mediation, but also to validate planning and support strategies invariant across age spans and different content areas. A first approach to basic mechanics, able to coherently and successfully evolve to higher formal levels, will exemplify model activation at school.