CHARLES DARWIN AND THE MYSTERY OF MYSTERIES, by Niles Eldredge and Susan Pearson (Roaring Brook 2010)(ages10+). A fascinating and eminently readable account of the life of Charles Darwin and the voyage of HMS Beagle.
Details abound, and the authors do a great job of showing how Darwin's experiences and observations led to the development of his theories on the origin of species.
The volume includes many figures and maps, as well as sidebars elaborating on the context of the narrative and of nineteenth century life. An excellent introduction to Darwin and his times.