Here's why:
* Different sources track sales differently: Some sources focus on print sales, others on digital sales, and some include audiobook sales.
* Sales data is not always public: Publishers often keep sales figures confidential.
* "Tween" is a subjective age range: What's considered "tween" can vary. Some might say ages 8-12, while others might use 9-14.
However, some of the consistently popular and likely top-selling tween books include:
* The Diary of a Wimpy Kid series by Jeff Kinney: This series has sold over 250 million copies worldwide and is a perennial favorite among tweens.
* The Percy Jackson & the Olympians series by Rick Riordan: This fantasy series is incredibly popular, with both print and digital sales topping the charts.
* The Hunger Games trilogy by Suzanne Collins: While technically YA, this series is often read by tweens and has sold over 100 million copies.
* The Babysitters Club series by Ann M. Martin: This classic series has been revived with a new generation of readers and has sold millions of copies.
* The Chronicles of Narnia series by C.S. Lewis: This beloved fantasy series has been enjoyed by generations of children and has sold over 100 million copies.
* The Magic Tree House series by Mary Pope Osborne: This adventurous series has captivated young readers for years, with over 150 million copies sold.
These are just a few examples. There are many other great tween books out there, and the best one for your child will depend on their individual interests.