The Godly Play method is a heavily researched method on how to teach kids about God and the Bible. It really has a lot of foundation for its methods. I love it for that. It really works and engages children on so many levels.
My disclaimer however is in the content of the actual curriculum books. There are certain things that I don't agree with, and lessons about things that just don't fit with my theology. Which is why I have chosen the people who teach these lessons carefully. I know that they are discerning and actually most of them have Bible related bachelor's degrees. I have given them the complete freedom to adapt the material to be more in line with the Bible, and they have on multiple occasions.
A few week's ago my husband, David was going to be teaching a lesson from the curriculum on Jonah. It said in the lesson that the story of Jonah was fictitious and written for the sake of comedy! He actually ended up rewriting the whole lesson to fit better with the BIblical account, and the lesson went really well.
Another teacher was doing a lesson on the exile. The material said that the purpose of the exile was to show the Israelites that God is everywhere. While it is true that they learned they could worship God in Babylon as well that wasn't the whole point of the exile. The reason for the exile was because the people had turned away from God and sinned. It was a punishment. This teacher made sure to incorporate that point into the story as well.
One other thing I have encouraged the people who teach with this method to do differently is to read from the Bible as well. In the Godly play method a storyteller is encouraged to not read at all. While this is excellent for the flow of the story, I think at the beginning or end it is still important to show the kids where they can go to see the facts and story for themselves. Which can also teach children how to use the Bible even before they can read.