There is a delightful little book series written and illustrated by Joey Allen. These book are fun, quick, little reads which take the little girls and guys into some sound theological waters in a unique way. Each book has another kid as a tour guide of sorts which takes the reader/listener through some Big Thoughts...

I think they could easily have been titled - Big Thoughts for making Little Thinkers as they do bring forth sound theological concepts for the kids. Just about every page has small Scripture references to be utilized by the parents. The volume on the trinity even has a copy of an ancient creed - Kayla and I read it getting loud and fired up about all the great doctrines and truths taught in the creed. Fun.

Here are links to the books where you can purchase. A must for every little persons theological libray:

Mr. Allen, if you read this I would suggest the following as additional titles, but I guess you may already have some in the works.

The Atonement - uniting the Old Testament sacrifices with NT teaching (ie Hebrews), and perhaps weave in all the intensions God has for the cross.
The Son of God - hit the hypostatic union, Jesus as Son of God, Son of Man, and the Messiah of Israel.
The Blessed Hope - not too specific as to avoid the post, pre, a, pre-mid-post stuff - but Jesus sure return as our blessed hope would be great.
The Covenants - That would be quite cool
The Holy Spirit