“It is my opinion that a young mind should first of all be occupied with sacred history and readings of the Lives of saints of your choice, which will unnoticeably sow the seeds of the fear of God and Christian life. You especially need to make them understand, with God’s help, how important it is to keep God’s commandments and what disastrous consequences follow when we break them.”
(Elder St Ambrose of Optina,  excerpt from his letters)