This beautifully illustrated educational book, part of the innovative SAE International - A World In Motion program, teaches engineering principles to primary-age children through an imaginative and exciting story. Once upon a time, all the trees on earth lived very close together. They enjoyed each other’s company until the ground got a little too crowded. Then they had a problem. But what should they do next? Only one thing was clear-they needed to make more room before it was too late. In Once Upon a Time in the Woods readers will learn the ways in which seeds are dispersed in nature, including how the wind propels them, how wind speed and seed weight affect the distance they travel.