Thank you for all your feedback. I love the idea notebook. We'll start that tonight. It's going to be fun to look back and see all his questions. We had started an idea notebook earlier but I wanted DS7 to write in it and he really doesn't like to write.
It's been a wonderful experience to learn with our sons but it can also be overwhelming for me. There is so much out there to read and do. We had almost 4 years of dinosaurs, which was really fun. Have you been to the Ology site to play the "Layers of Time"?
http://www.amnh.org/ology/index.php?channel=paleontology