As it is the parents who have given life to their children, on them lies the gravest obligation of educating their family. They must therefore be recognized as being primarily and principally responsible for their education.
The role of parents is of such importance that it is almost impossible to provide an adequate substitute… It is therefore above all in the Christian family, inspired by the grace and responsibility of the sacrament of matrimony, that children should be taught to know and worship God and to love their neighbor, in accordance with the faith which they have received in earliest infancy in the sacrament of Baptism.
Declaration on Education
Second Vatican Council