In this article the authors introduce "La main a la pate," an international programme based in France that focuses on enquiry-based science. Since 1996, the Academie des sciences in France has been engaged in serious intervention in order to renew science education in primary schools. Based on enquiry-teaching principles, and closely coordinated with a number of international partners, this action has progressively transformed elementary science teaching in France, although the goals have not yet been fully achieved. This action has progressively expanded, through collaborations with a diversity of countries, proposing resources and self-training tools for teachers. Since 2004 two European programmes, triggered by "La main a la pate," have linked and amplified the efforts and experiments carried on at national levels in other countries. Finally, in France alone since 2006, the development is also being pursued in a different context at junior high school level.