Parents and teachers in the church, teaching kids is a privilege, joy, and challenge. We want our kids to know the truth of the Bible at an early age to equip them as they go about in their daily life. There are great resources for the grown ups that have lasted for years. It only has been recently when more good resources for kids have become available especially theological issues.
Most churches avoid teaching kids theology like the plague. "It just doesn't happen," they say. We live in a day where our kids are getting hammered with non-Christian worldview that it would be ignorant to not teach children theology.
Here are some resource that are available for parents and church teachers can use (some of them are at reasonable prices right now):
The Ology: Ancient Truths Ever New by Marty Machowski
The Biggest Story: How the Snake Crusher Brings Us Back to the Garden by Kevin DeYoung
The Jesus Storybook Bible by Sally Lloyd-Jones
Everything a Child Should Know about God by Kenneth Taylor
Big Truths for Young Hearts: Teaching and Learning the Greatness of God by Bruce Ware