Cycles in nature

Explains how energy is transferred from plants to animals via the food chain.

Explains the growth and reproduction of plants, how dead plant matter is recycled, and how human actions affect plant life.

Explains the science of the changing seasons and describes the unique characteristics of the earth and living things during each one.

Describes the processes that create rock, such as weathering, compaction, and cementation, and examines igneous, sedimentary, and metamorphic rock.

Describes each of the moon's phases, explaining in text and diagrams why the moon appears as it does from Earth.