How Machines Work: Zoo Break!
by David Macaulay
I know you can't tell from this picture, but this book moves! The gear on the right is exposed and with a little help from the reader, the sloth goes up and down on his cool contraption. Most books about simple machines are pretty dull but this one has flaps, levers, and working gears! David Macaulay is a master at telling stories full of information and this one is about a sloth and a sengi who are trying to escape from their zoo home. Will they make it? What can they build to help them escape? You'll have to read (and play with) this book to find out.