Describes different kinds of materials, their composition and uses, how they are produced, and ways in which to recycle such things as paper, fibers, and metal.
Explains various aspects of energy including its uses, changes it undergoes, ways of conserving it, and energy sources such as nuclear, chemical, solar, electrical, and heat.
Introduces the food cycle and its importance, including how plants manufacture food, the plants, animals, bacteria, and fungi that make up the food cycle, and the fragile balance between feeding the world's human population and preserving the balance of nature.
Introduces Earth as a planet spinning in the solar system, how that has been misunderstood, and its myriad results including night and day, gravity, tides, and seasons.
