Charlie Thorne and the Last Equation by Stuart Gibbs

What’s the only way to figure out an equation left by the smartest human alive? Get a girl who is just as smart to figure it out. Charlie Thorne, who is only twelve, is given the task of helping the CIA track down an equation made by Einstein that could possibly destroy the world. But once Charlie figures out what the equation could be used for, she begins to question whether she should share the information. This book is so good! And I loved the 2nd book in the series too. I think people 8+ would enjoy this book the most. And I loved how even in a fiction book I learned so many cool and interesting facts. 5/5 stars for sure!