A review by bickie
The Unbreakable Code by Jennifer Chambliss Bertman

4.0

7th graders Emily and James are back, putting their sleuthing and decoding skills to use as they try their hands at a Gold Rush-era, fireproof unbreakable code while discovering a mysterious series of arson attacks linking the code, TOM SAWYER, their teacher Mr. Quisling, and the Book Scavenger game. This is a solid follow-up to BOOK SCAVENGER that, like its predecessor, is a special delight for San Franciscans. Best for ages 9-12 (a little more focus on who Emily is and how she wants to be in the world than the last one).