Host family for one school year excepted holidays

We are french and we live in Montreal, Canada, since 10 years. Our 16 years old boy will study in the Winston Churchill International HighSchool next year (1èreS) for one year to improve his english level and discover a new culture. We are looking for an host-family for him in the area of the school. He is ready to help with services as baby sitting or tutoring. The family could be payed against services or we would be happy to make an exchange and to invite another student one year in Montreal. He would be outside the family for holidays time.
Thank you to help us. Best regards.