Primary school students have trouble understanding concepts related to fractions. On the other hand, technology constantly provides interesting tools that stimulate students' interest and foster learning. Among these, tangible user interfaces allow users to interact with digital applications through the manipulation of everyday objects. Given that conventional tangible materials are already used in the teaching of fractions, the study at hand presents the results of a project in which their impact on learning was compared to that of materials digitally enhanced with the use of tangible user interfaces. The results indicated that the learning outcomes were better for the group of students who used the latter. Moreover, students' enjoyment was greater. However, there were no differences in terms of motivation, ease-of-use, and subjective learning effectiveness. The results can be attributed to both the characteristics of tangible user interfaces and the teaching framework that was followed. Nevertheless, the educational potential of tangible user interfaces has to be further explored.