Extreme Weather explains the causes of four different types of weather: droughts, floods, tornados, and hurricanes. While each of the four books focuses on a different type of extreme weather, the same key concepts are developed across books to help students focus on the big ideas. The theme explores the causes of extreme weather and develops an understanding of how meteorologists use cloud movement, tools, and technology to predict weather. Students use the specific content and vocabulary within each book to discuss and examine these big ideas, or Key Concepts. The Theme Set Program is designed for differentiated instruction. Each Theme includes four books written at four different reading levels.