National Geographic Primary Readers is a high-interest series of 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 six reading levels.This Set contains 17 readers across 2 levels:Level 5: Confident readersPerfect for children who are confident in reading independently and are ready for the challenge of varied sentence lengths, some technical vocabulary and increasing inference.Level 6: Skill readersIdeal for children who are very confident in reading independently and ready to challenge themselves with a wide variety of sentence structures and writing styles, a range of new technical vocabulary and the need for more complex inference.