How do plants make oxygen? Why do the seasons change? How are different types of rocks created? In this series, readers will learn about the various cycles that happen on Earth. Each book utilizes accessible language to break down scientific concepts and informative graphics to show readers the cycles in action. This series also addresses the significance of each cycle and its relationship to others, while looking at what would happen if the cycles were imbalanced. Additional features include a table of contents, a phonetic glossary, an index, and sources for further research.