Wow - so sorry I confess I forgot about this!
"but am more looking for questions to ask and ways to steer a conversation appropriately"
One way I saw a teacher handle a similar scenario (regarding evolution but the point I think stands) was not to take on the theistic attitude at all. They sort of called a halt and just said "I'm not going to argue or say anything about that. I'm just going to go through the evidence because that is what scientists do, they examine the evidence."
Too late now obviously to be much good,, but Keri, if you are still around, please tell us how did it all work out in the end?
You might not want to start out with "what do you think" if you're pretty sure that your students will point you toward the biblical story. Maybe start out with some theories, and ask the kids "how do you think scientists came to this conclusion?"
Go about it the scientific way, and emphasize that all the information is based on evidence (give as much as you feasibly can). If the students ask questions about god, tell them that since their parents or church can better answer that questions. If parents call up, say basically the same thing. You teach information based on observable and logical evidence. If the parents have anything to add, they should be telling it to their child.