Complex sentence: The school attracts students from all regions of the world, especially countries in the Francophonie, however the powerbase remains in the hand of upper middle class families from Toronto, both Francophone and Anglophone.
Split into simpler sentences: The school attracts students from all regions of the world, especially countries in the Francophonie. However, the majority of students are of upper middle class families from Toronto, both Francophone and Anglophone.