"Within family-centered catechetical programs are opportunities for parents to catechize their children directly, for spouses to catechize each other, and for children to catechize one another and their parents. Family catechesis should include prayerful celebration within the family that is closely linked to the liturgical celebration of the parish. It should include opportunities for Christian service within the family and the neighborhood, which at the same times disposes the family members to render service in the name of Christ to the whole human family."
National Directory for Catechesis 61A-2
Family Catechesis comes in many shapes and sizes. Catechist Journey Archives can provide a good place to start with a variety of articles and resources on the topic.
From Sadlier check out this page with a variety of alternative models for Catechesis. You can download some excellent resources; look especially for the 'Family Centered Model' resource.