Biosphere reserves promote twinning between primary and secondary schools both in France and internationally. Teachers (or teams of teachers) determine a theme together, e.g. water, forests, food security, etc.
During the school year at least, classes participate in activities which lead to exchanges by mail, Internet or other means of communication. Various subjects can be covered: written and oral expression, art, mathematics, sport, history, geography, science, etc. The idea of twinning is to encourage group and individual work, solidarity, and respect for self, others and the environment. Sometimes the students even end up meeting each other.