God's covenant with His people is intended to be a perpetual one. It was not intended for one generation only. Understanding of God's covenant with His people does not automatically transfer from one generation to the next. The individuals within each succeeding generation must be taught the meaning of the covenant and invited to enter that covenant relationship with God personally. The work of parents underlies every other.
Society is composed of families, and is what the heads of families make it.
Deuteronomy also attaches importance to teaching within the family in a number of it's verses. The home is to be the center for conserving and propagating truth. Moses understood that the greatness of the nation depended upon the teaching of God's Word in the home. Verse seven has the answer. Talk about them when you sit at home and when you walk along the road, when you lie down and when you get up.