The study of learning processes in the artistic disciplines was, in the 1960's, the principal concern of Nelson Goodman. This vast research project named "Project Zero" very quickly expanded to many other disciplines. The pedagogical approach called Teaching for Understanding developed by Project Zero deals in particular with the phenomenon of comprehension within the learning process. What does it mean to understand something? What do we want our students to understand? A pupil demonstrates comprehension of knowledge (to know, know-how, etc) when he/she is able to apply this knowledge. To understand something is to see it from new perspectives, and to use it in pursuit of further knowledge and to do this autonomously. Four strongly related components ensure the coherence of the methodological and teaching framework and provide opportunities to reach a true comprehension. Teaching for Understanding is now the methodological and teaching framework of reference for many teachers on the other side of the Atlantic and for certain International schools in Europe . The central goal is a deeper understanding of the knowledge, rooted firmly in the reality of the learner.