Sara and Daniel, 6th-grade cousins and best friends, are famous in their community for foiling a group of bank robbers with their own secret code on the first field trip of the school year. But that excitement has blown over. Now they''re looking to the new lunch clubs, a charity event picking oranges, and Kevin, the new kid in school, to find something that will make the school year more interesting. When Daniel gets framed for vandalism at the school and they learn about mysterious thefts from the nearby perfume factory, life does get more exciting, but not exactly in the way they''d hoped. Sara, Daniel, and Kevin throw themselves into the school activities and work to solve the crime using math and engineering ideas they pick up along the way. Discovering a fascinating world of optimization, radio frequency identification tags, and sphere packing in multiple dimensions, the kids find that Science, Technology, Engineering, and Math (STEM) skills can be useful in some very unexpected ways.This is Pamela Cosman''s second book for children and is a follow up toThe Secret Code Menace. With a story that is both intriguing and puzzling, this book is perfect for children who want to read something out of the ordinary, something different to the usual range of books on offer for their age group. As part of our Cold Fusion series, it is a relatively short read, but still has a compelling plot and offers plenty for the reader to think about, so it''s perfect for more able reluctant readers.