Collaborative learning systems offer common virtual spaces where different users (i.e. teachers, students, school directors, parents, researchers, and experts) can interact. Participants can share their pedagogical, technical and administrative knowledge. CONEXIONES project, a research group that has been enhancing the learning process in Colombian schools through the use of new technologies, has developed COLEGA, a collaborative and learning tool to support knowledge evolution processes within learning communities. This paper presents COLEGA, a collaborative and learning tool that integrates retrieval document algorithms based on keyphrases, synchronous and asynchronous communication tools, and support for evolving individual and group memory. Results of a usability study are also presented in this paper.