Cambridge Discovery Education Interactive Readers are the next generation of graded readers - captivating topics, high-impact video, and interactive exercises designed to motivate and engage. The ancient world had seven "wonders" - amazing things made by people. Today, people don't agree about what the biggest wonders are. What do you think is a wonder? Use the unique code inside the book to access the online reader, complete with videos and interactive exercises. Plus, download a free e-book version of the reader!