This paper problematizes what can happen when different practices meet in the mathematics classroom. In an educational design research project, researchers and teachers together promote students’ participation in mathematical dialogue through the use of digital tools. Tensions on what is put in the foreground – the mathematical dialogue or the digital tool - as well as tensions of how students can be included or excluded in the dialogue, are analysed using the Learning Design Sequence model. Through the analysis of tensions, further areas for improvement can be identified.