This article reports on a research project, which was part of the research- and development project World Class Math and Science. The objectives of this part of the project were to research the potentials of computer use in upper secondary school mathematics for the teaching of differential equations from a modeling point of view. The project involved small scale teaching experiments with changes at two levels from the traditional viewpoint on school mathematics: 1) Change of view at curriculum level on the subject differential equations and 2) Change of view at the level of didactical reflections on the intentions of modeling and using models. The article discusses how students’ use of laptops can serve as a means for both changes by replacing complex, time consuming expressive modeling with more controlled exploration of differential-equations models. Finally, the perspectives for the teaching and learning of mathematics of such changes are discussed.