This research study investigates several cases of linguistic variation occurring in the spoken French of Franco-Ontarian adolescents, with the primary goal of examining how these cases of variation relate to levels of French language use restriction and contact with English, as exhibited by these adolescents. More specifically, the present study focuses on variation in the use of the French preposition 'de' preceding the deictic pro-forms 'ça' and 'là', variation in the use of 'aller' in the 'passé composé ' and the 'plus-que-parfait' tenses and variation in the use of French prepositions 'à, au' and ' en' followed by geographical place names. The informants observed in this study were taken from the Mougeon and Beniak corpus of Grades 9 and 12 Franco-Ontarian students enrolled in French-medium high schools in four Ontario localities (Cornwall, Hawkesbury, North Bay and Pembroke) where Francophones represent varying proportions of the local population (85% to 8%).