Nina and the Keeper of the Keystone

Secret Society of Rebel Girls

Illustrated by Kristina Kister
Hardcover
$16.99 US
On sale Oct 14, 2025 | 256 Pages | 9798889641162

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Book two in the exciting fantasy chapter book series from Rebel Girls has more adventures in store for Nina and her friends!

An after-school job.
A sinister superintendent.
And advice from…Ruth Bader Ginsburg?
Growing up is getting complicated!

Now that the Three Musketeers (and Kai) are best friends again, this is going to be the best year ever! But Nina’s friends all seem to want her to take charge when all she wants to do is blend in. And on top of all that pressure, she’s keeping two fluffy little secrets from her moms...

When the school’s new superintendent ignores what the kids want, bringing in uniforms, shutting down clubs, and getting the best teachers in trouble, it’s time for action! Luckily, Nina and her friends can turn to the mysterious mailbox for answers, and soon they have Ruth Bader Ginsburg’s advice in hand. Will it be enough to save Ada Lovelace Middle School and Ms. Jupiter? And will Nina finally feel ready to be a leader?

Don’t miss the first book in the Secret Society of Rebel Girls series:
Nina and the Mysterious Mailbox
Rebel Girls is a global, multi-platform entertainment brand, dedicated to inspiring and instilling confidence in a generation of girls around the world. Rebel Girls started from a 2016 international bestselling children's book, featuring real-life, extraordinary women throughout history, geography and field of excellence, focusing on creators, innovators, leaders and champions. Its community of self-identified Rebel Girls spans more than 100 countries, with six million books sold in 51 languages and 13 million podcast downloads. View titles by Rebel Girls

About

Book two in the exciting fantasy chapter book series from Rebel Girls has more adventures in store for Nina and her friends!

An after-school job.
A sinister superintendent.
And advice from…Ruth Bader Ginsburg?
Growing up is getting complicated!

Now that the Three Musketeers (and Kai) are best friends again, this is going to be the best year ever! But Nina’s friends all seem to want her to take charge when all she wants to do is blend in. And on top of all that pressure, she’s keeping two fluffy little secrets from her moms...

When the school’s new superintendent ignores what the kids want, bringing in uniforms, shutting down clubs, and getting the best teachers in trouble, it’s time for action! Luckily, Nina and her friends can turn to the mysterious mailbox for answers, and soon they have Ruth Bader Ginsburg’s advice in hand. Will it be enough to save Ada Lovelace Middle School and Ms. Jupiter? And will Nina finally feel ready to be a leader?

Don’t miss the first book in the Secret Society of Rebel Girls series:
Nina and the Mysterious Mailbox

Author

Rebel Girls is a global, multi-platform entertainment brand, dedicated to inspiring and instilling confidence in a generation of girls around the world. Rebel Girls started from a 2016 international bestselling children's book, featuring real-life, extraordinary women throughout history, geography and field of excellence, focusing on creators, innovators, leaders and champions. Its community of self-identified Rebel Girls spans more than 100 countries, with six million books sold in 51 languages and 13 million podcast downloads. View titles by Rebel Girls

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