"Introduces the oxygen cycle and its impact on Earth. Readers will gain insight into how oxygen is created and used, what happens when it combines with other elements, and how human activities have impacted the cycle"--Provided by publisher.

"Describes what rocks and minerals are."-- Almost as old as our planet, rocks are formed and shaped by heat, wind, water, and immense amounts of pressure. You can see the evidence of their long and violent history in their color, shape, and texture. In addition to rocks, Earth is full of minerals. In fact, rocks themselves are made out of minerals. These are naturally occurring solids found in the earth.

"In Rocks, beginning readers are introduced to the rock cycle, how sedimentary, metamorphic, and igneous rocks form, where we can find them on Earth, and how people use them in everyday life. Vibrant, full-color photos and carefully leveled text engage beginning readers as they learn how rocks form and change. A picture diagram shows the rock cycle, while a picture glossary reinforces new vocabulary. Children can learn more about rocks online using...