The paper discusses the differences between teaching CAAD by using standard software (“off-the-shelf”-software) and teaching the principles of CAAD (“principles-teaching”). The paper distinguishes four kinds of application for design systems in education: social systems, professional systems, educational systems, and innovative systems. The paper furthermore proposes to distinguish between computational issues and architectural issues relative to design systems. It appears that there is not a principled distinction between software-teaching and principles-teaching when it comes to computational issues of design systems. However, when the architectural content of CAAD systems is concerned, then principles of CAAD systems seem to be more appr...