Résumé
Relying on the collective work carried out in the e-CoLab project concerning the experimentation of the new calculator TI-nspire, we address the issue of the relationships between the development of mathematical knowledge and instrumental genesis. By analyzing the design of some resources, we first show the importance given to these relationships by the teachers involved in the project. We then approach the same issue from the student's perspective, using some illustrative examples of the intertwining of these two developments framed by the teachers' didactical choices.