When I was at Bethel Seminary a few years ago, in my Introduction to Children and Family Ministries class, my professor talked about 3 powerful ways to form faith in our families.
She got this information from the Search Institute:
Talking with Mom or Dad about faith
These are informal conversations that happen in the course of everyday life.
Participating in family devotions, bible reading or prayer
This is an intentional time of setting aside time (everyday, 3-4 times per week, or at the minimum once per week) to read the Bible and pray together as a family.
Being involved in family service projects
Serving alongside of each other as you enact the kingdom of God in our world.