This collaborative research was carried out among 197 elementary school students, in the context of a rural Canadian school of the Quebec province. Several students of the school presented learning difficulties, mostly in writing. The teachers and the learning specialist decided to differentiate the groups in special subgroups of needs that met for a half-day once a week; they also implemented the explicit teaching of writing. The results showed that there was an important improvement in all the students' writing ability, especially of those with learning difficulties. Indeed, the subgroups of students with severe learning difficulties showed a significant reduction in the average error rate. The dialogue among the teachers, the learning specialist, the director and the researcher was a key component for the success of this project, which aims mainly to accompany the teachers and to encourage the effective integration of students with learning difficulties. (Contains 14 figures.)