Joelee Chamberlain made a Creation audio for children, "The Master Builder", which is on Sermon Audio. It gives the argument for the Creator from cause, design, and contingency for 4-5 year olds in 25 minutes. She also presents the Gospel pointing to the brokenness of the world and that God is the Master Re-Builder. She presents mostly arguments from design of man, the world and the solar system, but at a level that a 4-5 year old could understand but without bringing up any doubts.I downloaded it and listened with my son. He enjoyed it especially some of the facts it introduced. Chamberlain does quite well, I would agree with most of the sermon. I disagree with the analogy of energy for machines and God's sustaining power she uses, but this is a minor dispute. It is definitely targeted at the age level mentioned.
I am not certain my readership is large enough to modify download frequency but I am happy to provide a link. You do not need to sign up to the newsletter to download. Here are her other children sermons.