In this article, we explore the potential of the computer to support curriculum materials development within the context of secondary level science and mathematics education in southern Africa. During the four-year course of the study, a computer program was developed named CASCADE-SEA, which stands for Computer Assisted Curriculum Analysis, Design and Evaluation for Science (and mathematics) Education in Africa. By carefully documenting the iterative process of analysis, prototype design, evaluation, and revision, we sought insight into the characteristics of a valid and practical computer-based tool that possesses the potential to affect the performance of its users. The results of this study include the CASCADE-SEA program itself, which assists users in producing better quality materials than they otherwise might, while they also learn from the development process. Further, this research has contributed to the articulation of design principles and related developmental research methods. This article highlights the research and development that took place, and only briefly addresses the tool itself.