Instrumental orchestrations : definition, defense and illustration

International audienceThis contribution is part of the thematic afternoon about "Technology in Mathematics Education", chaired by Paul Drijvers and Kaye Stacey. It focuses on the issues of instrumentation and orchestration, which are not really specific to the field of Computer Algebra System.The main issue is to build and to combine, within mathematics learning processes, various instruments. It is not a new issue, as well for mathematics and mathematics education, all the more true in periods of transition