Written by #1 New York Times best-selling author Rick Riordan, this book is the first in a series of ten books. The books will be accompanied by 350 collectible cards and a dynamic online game — called 39 Clues — where readers can compete for prizes. Kids will embark on an adventure tracking their points and their clues, managing their card collections, digging through the Cahill archives for secrets and “traveling” the world to collect Cahill artifacts, interview characters and hunt down clues. Scholastic will be giving away more than $100,000 in prizes. Launch date: September 2008.