Throughout history, various groups have developed catechisms for helping bring new believers along--including catechisms for children. I'm not going to say any are right or wrong--each have their benefits and if one way was perfect then I'm sure God would have put it in the Scripture.
In doing some research for another topic, I ran across an ancient Jewish source (m.'Abot 5:21) which provides an interesting approach to aging and growing in the faith.
I modified it slightly to make it Christian, and present it here just as a thought-provoker:
Five Years Old: Begin teaching the Scripture, with Bibles appropriate to their age and understanding level. At this age they will surprise you with what they can understand: by six, my youngest was asking Sunday School teachers to explain the Trinity. So don't hold back on going into some basic details and how they connect to the grand story of Scripture.
Ten Years Old: At this age, Jews began to teach their children the Mishnah. The Mishnah is essentially a study of the teachings of the Jewish tradition (dietary laws, prayer, etc.). It is divided into six basic categories, of which I think all but the one on Jewish ritual purity are useful for Christians as well:
- Seeds - teaching prayer and generosity
- Festivals - teaching the concept of Sabbath and celebrations of the faith (Easter, Christmas)
- Women - teaching about marriage and divorce
- Damages - teaching about civil and criminal law and courts, and how to interact with them
- Holy things - teaching about proper behavior, rites (baptism, communion)
Thirteen Years Old: At this age, the child is seen as becoming accountable for following the commandments. By now he or she should be mature enough to exhibit self-control and follow the teachings of Jesus in their lives. From now on they are considered a "youth."
Fifteen Years Old: At this age, the youth begins to study commentaries and begin to understand basic theological techniques--that is, how to interpret and study the Scripture and how others have done so.
Eighteen Years Old: At this age, the youth is old enough to marry and begin to raise a family.
Twenty Years Old: At this age, the youth should begin to pursue their calling. In the next ten years they should have established their career and completed all apprenticeships.
Thirty Years Old: At thirty, the youth becomes an "elder" or full-grown man/woman. Now they are allowed to be in leadership roles, teaching positions, and exercising authority.
Fifty Years Old: At fifty, the elder has experienced enough to become a counselor to those younger than him.
Sixty Years Old: From sixty on, the elder enters "old age" and is to be freed from responsibilities to enjoy retirement. He or she should be shown the upmost respect and can still be very valuable as an advisor.
Again, this is nothing magical. But it is interesting to me, particularly at the younger ranks. I think that we today are far too slow with educating our children in the faith. Many Christians don't even think about starting to teach Scripture until a child is into their teens; whereas by 13, a typical Jew or early Christian would have been in their 8th year of Scripture memorization and already had three years of learning how to follow the basic disciplines of the faith (prayer, quiet time, the meaning of rituals/rites, etc.)