Summer reading has really paid off for 66 lucky kids who won a combined $8,150 in The 39 Clues global adventure. To date, more than 560,000 kids have registered at www.the39clues.com to digitize cards, play games and earn points.

This round’s top winner was 10 year old Kyla from Atlanta, who won $1,000 as the first prize winner of the Book #3 Episode Contest: “I love when I get missions. They are so fun to complete and you get a clue at the end!” she said.

But there's much more to The 39 Clues than the books, cards, and game. With a plot that's steeped in history and geography, The 39 Clues is also a powerful educational resource. Check out how one teacher is using the series as a classroom tool (and winning awards for his work): click here to watch.

The fifth book in the series, The 39 Clues: The Black Circle, was released on August 11, 2009.