Symba is a Web-based framework designed to support collective activities in a learning context. It has been constructed with a double objective, (1) make students explicitly work out their organization and (2) provide tailorability features to allow the students to decide about the tools and resources they want to be accessible in order to achieve the tasks they have defined. Symba dissociates an “organizational level” and an “activity level”. The organization level allows students to organize their activity as a set of phases, each phase being structured as a plan (sequence of tasks). When expliciting a task, students can define the tools and the resources that should be available at the activity level to achieve it. This allows combining the two objectives: students can benefit from an activity level tailored according to their wishes by explicitly defining their organization.