Every year about this time I start hearing people question whether, as Christians, we should include Santa Claus in our celebration of Christmas. We exert so much effort in trying to get the world to remember the "Reason for the Season", and to "not take Christ out of Christmas", it seems foolish that most of us will then exhort our children to "tell Santa what you want" or "go to bed so Santa and his reindeer can come." Personally, I like the tradition of Santa. As with anything, Santa can be misused. I believe that we, as Christians, can use Santa to teach valuable lessons to our young children.
Christ extols love and charity. We can use Santa to teach our youngsters these same virtues. Although young kids are much more excited by what gifts they are getting than what is being given to others, allowing them to see our own excitement at both giving and receiving can teach valuable lessons. It is OK, when working with the very young, to use the "Jolly Old Elf" to teach the valuable lessons of love and kindness. Don't worry about your child growing up to worship Santa instead of Jesus. As they mature, they will naturally understand the difference between make-believe and reality. They will no longer enjoy hearing about Peter Rabbit and Donald Duck, instead wanting to read Huckleberry Finn and Nancy Drew. In fact, in most cases (certainly with my four children) your children will stop believing in Santa without any help from you. It will just happen (usually before puberty.)
HOWEVER, Do not delay teaching your children about Jesus. They should start hearing the wonderful stories of the Bible at a very early age. Just remember what the Bible says about Santa. "When I was a child, I spake as a child, I understood as a child, I thought as a child: but when I became a man (an adult), I put away childish things." 1 Cor. 13:11