ciphers

"Amid assignments that take the Explorer Academy recruits from the iceberg-filled waters of Antarctica to the bone-dry deserts of Argentina, Cruz Coronado is scrambling to complete the last piece of the cipher. With Nebula agents and the elusive explorer spy still out there, his opportunity to recover his mother's world-changing formula is slipping away. But as Cruz has learned from his time aboard Orion, true explorers must never give up. Even after completing dozens of high-risk missions and traveling to all seven continents, Cruz could never prepare himself for one ultimate surprise"--Provided by publisher.

Cryptology is the art and science of secret communication, and its purpose is to protect precious information and keep people safe. Learn about its building blocks: ciphers, codes, and keys.

Steganography is the art of concealing messages in plain sight. Read about invisible inks, the Cardano Grille, the use of microdots in WWI, and the butterfly maps of Lord Baden-Powell.

"On an island nation in the Indian Ocean, the explorers venture through a vast underwater world and take part in a friendly robotics competition. But the tides of good fortune change quickly. Suddenly, Team Cousteau jumps into action to rescue a faculty member from the brink of death. Meanwhile, the team follows the Cruz's mother's clues to a magnificent tomb and center of spirituality precariously perched on the side of a cliff. There, Cruz is confronted by a familiar foe who's determined to stop him from completing his most important mission of all: Retrieving the final pieces of his mother's cipher. In this life-or-death showdown, Cruz witnesses the ultimate sacrifice and uncovers a hidden message that makes him question his own mortality"--Publisher.

"Still reeling from the life-changing discovery he found buried in the mysterious archive, Cruz Coronado grapples with an important secret as the gang heads to China in search of the second-to-last piece of the cipher. Under the watchful eye of a new adviser, life on the ship returns to almost normal . . . Almost. Just as things seem to be going smoothly, a familiar face shocks Cruz back into reality, and the final piece in this life-and-death scavenger hunt veers toward a dead end"--Publisher.

Akiko, Mae, and Josie, also called the Infinity Trinity, spring into action after learning that a spy is betraying secrets to the Japanese military--and that Akiko's mother may be involved.

"Marly, Sai, and Isla are back on the hunt. After finding Mr. Summerling's hidden treehouse, they've discovered a new set of clues for them to follow, leading them straight to the heart of their mysterious neighbor's life: his house. The same house Marly has been living next to all of these years, which, they discover, is filled with hidden rooms and staircases. With just a few scraps of papers as clues, and Mr. Summerling's angry son on their tails, can the Treasure Troop find the answers they're looking for?"--OCLC.

Logan tells Quinn that he likes breaking codes so she gives him a coded message. In truth, Logan isn't a code breaker and now he has to find a way to break the code or admit the truth.

"Chris and Carrie have been betrayed. Maddison has discovered the dark secret in her father's past. A cold case is suddenly hot and has changed from 'missing' to 'murder.' As a crime wave hists Archer's Grove and authorities struggle to catch the culprits, Chris, Carrie, and Maddison turn to the Kinsolvers' Aunt Elsie for answers. Can the notebooks she left behind illuminate this tangled web of lies, betrayals, and broken promises? Will the truth finally be uncovered?"--Proved by publisher.

Twelve-year-old Addison Cook and his friends are on the hunt for a long-lost treasure. They'll need to outwit a band of thieves, survive booby traps, crocodiles, and a Russian assassin--to name a few of the obstacles standing in their way--in order to secure the three keys needed to unlock the ancient treasure.