National Geographic Primary Readers is a high-interest series of beginning reading books that have been developed in consultation with education experts. The books pair magnificent National Geographic photographs with lively text by skilled children's book authors across four reading levels. In this level 3 book, young readers explore the amazing underwater world of coral reefs. Level 3: Becoming independentBest suited to kids who are ready for complex sentences and more challenging vocabulary, but still draw on occasional support from adults. They are ideal for readers of Purple and Gold books.