Lucas, a little boy who loves ladders, becomes sad when he is repeatedly told it is not safe for him to climb, but his father finds him a ladder that is just right.
Examines ways in which the world is experimenting to produce enough food for its growing population, including farming the sea, new agricultural methods, and new ways of keeping food fresh.
Illustrates why air is important to plant and animal life, discusses how certain inventions have depended on it, and suggests activities demonstrating its properties.
