This paper presents the core concepts of the ISiS model (Intentions, Strategies, and interactional Situations), a conceptual framework elaborated to structure the design of learning scenarios and promote sharing among teachers-designers. This model, co-elaborated with final targeted users and inspired by recent works in the field of goal-oriented requirement engineering, makes explicit the intentions and strategies of the designer. The ScenEdit environment enables practitioners to graphically design their scenarios making explicit the different dimensions associated with the ISiS model. ScenEdit aims at favouring sharing and reuse of practices by providing, for each type of model component, patterns issued from the literature and/ or co-des...