In a School of Engineering scientific and technological knowledge live together. Science teachers usually try to understand the role that scientific disciplines have over the engineer training. In this paper are descript three historical case studies that could help teachers and students for better understanding the interdependence between science and technology, and the way in which both are related to society. The cases clearly show that both kind of knowledge, scientific and technological, are autonomous, and that their growths involve complex processes. On this way, learners could have an insight of both, the NOS and the NOT.