I have just finished the 4 books that make up the City of Ember series.
They are a great read with plenty of action and thought provoking ideas.
All of the books look at issues of war, conflict and the courage needed to stop them from happening.
What is great about these books is that it is intermediate-aged heroes who challenge adults into making the "right" decisions for us and our planet.
The issues are real and the courage needed to solve them will be needed by our generation or the consequences will be devastating.
Check these out at the school library - Mr Marsh