Michael Riess examines the qualitative differences in the construction of mathematical knowledge following a lesson with digital tools. To this end, he first develops a model of influence based on general learning theories, which outlines the impact of the tools used in mathematics instruction on individual mathematical concepts. This model serves as the foundation for designing the empirical study, the results of which provide insights into the potential answers to the research question within the context of the developed theory. The author identifies different ways of thinking, solution strategies, and uses of mathematical representations, demonstrating that the observed differences exhibit characteristics that extend beyond the use of different action schemas. This supports the assumption that the use of various tools leads to fundamental changes.