Deep underground is a fascinating world of caverns filled with crystal formations, secret lakes, and hidden creatures. SPECTACULAR! Caves answers young readers' questions about how caves form and what mysteries they hold. The Spectrum® Readers are the perfect Common Core aligned tool to support the development of nonfiction reading skills. Each leveled reader features high-interest informational content, exciting full-color photo images, and Common Core aligned comprehension practice focused on the development of critical thinking skills. Leveled to the respected Fountas and Pinnell and Lexile systems, these 32-page books are perfect for young readers who are ready to explore leisure reading on their own. This multilevel series is the perfect addition to any school or home library.