Schools and teachers increasingly apply Online Learning Environments for teaching and course management. In many cases, an existing platform is used to support the curriculum. At the K.U. Leuven in Belgium a campus-wide platform is provided, using a commercial Content Management System. At the same time, the Design and Building Methodology research group at the Department of Architecture, Urbanism and Planning developed a custom portal to organize Computer Aided Architectural Design courses and seminars. Integration of this portal into the university system was rather disappointing, since much of the flexibility and customizability was lost, without any chance of filling in the gaps. This article discusses the possibilities and limitations of existing web-based systems to support Computer Aided Architectural Design teaching and reports on our own experiences from the last decade. A comparison of selected systems is juxtaposed with the requirements derived from these experiences.