We read Hatchet by Gary Paulson for our adventure story. When we've completed the book, I have them write their own adventure story using a guide that I designed. They really enjoy the book and writing their own adventure.
We also read Mr. Tucket also by Gary Paulson. It could be used as an adventure book, but we usually use it when we cover the Westward Expansion unit.
You said you'll be reading The City of Ember. That is a great book, too. Our fifth grade team uses it as a read aloud when we do our unit on electricity.