It is well established that Web-based courseware must not restrict itself to the mere delivery of instructional material, but must be grounded in some sound model of instruction and learning. This paper discusses one such model, based on the best of instructional design principles and tries to overcome two of the most serious problems that are being faced in the process of introducing interactive Web-based learning, namely disorientation and cognitive overload. Whereas the emphasis in a lot of recent work has been on digital technology reuse, the emphasis is on core aspects of the content development process. The principal contribution is an intuitively clear iconic notation that can be used to templatize and thus simplify the task of educational content development. The paper briefly describes the evolution of this model, the experimental effort to evaluate this model and the courseware development process that was adopted. (Contains 13 references.) (Author)