The report, entirely in French, presents a study of the instructional approaches used for French native language instruction at the elementary and secondary school levels in five regions of Ontario (northwest, northeast, mid-north, central, and east). It examined the nature and degree of linguistic heterogeneity and the distinctive traits of the linguistic groups in each of these regions and the cultural differences that influence the choice of instructional approaches and teaching methods. It then focused on the relationship between the administrative structures in place and the capacity to use strategies supporting the use of French. Finally, it examines the conceptual elements that can help establish a policy of language maintenance that encourages the blossoming of student skills in a linguistically heterogeneous environment and sustains a consistent educational vision in Ontario. (Author/MSE)