For more than thirty years-half his life-he was obsessively devoted to investigating everything in the natural world. Nothing escaped his interest-how our eyes see, why the sky is blue, what forces build mountains, how light travels, where water comes from, and-most fascinating of all to Leonardo-the inner workings of the human body. Nothing stopped him. It was illegal to dissect human corpses, so he did autopsies in secret, even devising a clever way to slice through eyeballs (notoriously squishy!). Scrupulously researched and juicily anecdotal, Kathleen Krull's portrait of Leonardo will not only change children's ideas of who he was, but also what it means to be a scientist.

So many things unknown! -- The outsider -- The desire to know is natural -- Nothing but full privies -- Lying on a feather mattress -- The universe stands open -- Citizen of the world -- The fabulous notebooks -- The fabulous notebooks, part 2 -- "I have wasted my hours" -- I will continue -- What happened next? -- Leonardo's notebooks and where they are now.