In the form of blog-posts, we provide some theoretical background about collaborative learning and place the topic in the context of Self-Determination Theory. From this theory, we came to develop a group self-evaluation procedure that we tested in high schools for four years. We share our experiences with this evaluation procedure. Based on our findings, and those described in the literature, we urge educators to make group evaluation part of collaborative-learning projects. By doing so, social skills, which provide the essential added value of this type of education, also get a place in the assessment. What we describe for education also applies, in our eyes, for collaborative projects in work-organization. In this context, learning and working are two of a kind. Read more in our Blog “group working & motivation”.