What do we know about what teachers do before they teach their students? In this vague area, when students’ activity has yet to take place, teachers may redefine their tasks in a thousand ways between resumption of the same and creation of new materials. Understanding teachers’ preparation phases and the resources they use is one of the aims of the ReVEA project. More precisely, this project seeks to document the various modalities of teachers’ activity and their motivation. It questions in particular the modes of organization, the means and tools used to search, select, transform, and save resources. Neither the data nor the intermediate steps in the production of resources are readily available. What we get by means of interviews are partial and subjective. However, our results show a large variability of practices. To illustrate this result, we focus in this text on eight physics and chemistry teachers all teaching in French secondary schools. We present their profiles obtained by means of semi-directive interviews, a few classroom observations and sometimes activity sheets given to students. We describe how they search and select between a multitude of pedagogical resources, how they take into account different time scales (the next classroom session, week, annual schedule), how they transform the resources, and in what way their work organization evolves or stabilises (storage, format). We try to understand the influence of training, heritage, important encounters, interest centres or the institutional or material environment (national curriculum, educational establishment, lab materials). Finally, it seems that independently of the constraints in their environment, teachers are mostly guided by personal motivation