Promoting the sharing and reuse of school resources is a complex issue which entails preparing teachers to adopt new ways of working. Due to the lack of a tradition in this sense, it is not easy to figure out what kind of teacher training can really prove successful to this end. This work describes an experience we carried out in a teacher training course on basic ICT, where we are trying to set up meaningful activities on the preparation and use of educational Learning Objects. In this paper we focus on a study devoted to explore the conceptions of trainee teachers as concerns the preparation and reuse of educational modules, which allowed us to spot points that require special attention and should be explicitly addressed in teacher training programs. We also outline some activities that we consider suitable to address the needs emerged from the mentioned study.