Interdisciplinary processes are being developed for a better present and future in primary and secondary education teaching in France. Over the past few years, the education authorities have increased incentives to open the subjects for one another and created new teaching-learning programs for interdisciplinary purposes. In spite of the obvious determination from the Ministère, the results of research on daily practices, as well as most of the official reports, show that the teachers of primary and secondary schools experience real challenges in implementing truly interdisciplinary teaching-learning activities.