Cruz, Sailor, Emmett, and the gang are on their way to Africa when Nebula misses their intended target and someone close to Cruz ends up on the brink of death. Secrets creep out from the shadows and leave Cruz with more questions than answers in this fourth title in the hit series. A major discovery forces the Explorer Academy into the limelight in The Star Dunes, but Cruz has much more on his mind than 15 minutes of fame. A new face on board the ship brings Cruz's worlds colliding, just as a major close call tears them apart. En route to Africa, Team Cousteau is now down a major player, and Cruz can't help but be preoccupied by the hole in his life. The discovery of his mum's next clue leads him to the most exotic location yet, a vast desert with no other information to lead the way, while an unlikely ally might be the clue to solving the next puzzle. Just as things seem like they might turn out all right, Dr. Fanchon Quills has a technological breakthrough which gives Cruz a glimpse into the past and reveals more about his future than he may really want to know.

The mystery deepens and the action intensifies for 12-year-old Cruz Coronado and friends in the exciting third book in the Explorer Academy series. The adventure continues for Cruz, Emmett, Sailor, and Bryndis as they continue their studies at sea and travel to exotic locations around the world. A mysterious person alerts Cruz to impending danger while he and a few trusted pals explore ancient ruins in Petra, Jordan, and search for another piece of the puzzle his mother left behind. Worst of all, now his father has gone missing, which prompts Aunt Marisol, his #1 protector, to leave the ship in search of him. Who is the new professor who takes her place? How does the new technology he introduces help or hurt Cruz's quest? Why is Nebula determined to stop Cruz before he turns 13? The clock is ticking as his first teen birthday draws near ... a milestone that will change his life forever, one way or another.

An explosive revelation and a familiar face in the sixth book in this adventure-packed series. 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. Explorer Academy features: * Gripping fact-based fiction plot that inspires curiosity with new technology and innovations * Amazing inventions and gadgets * A cast of diverse, relatable characters * Secret clues, codes, and ciphers to track down within the text * Vibrant illustrations * Elements of STEAM * National Geographic explorer profiles in The Truth Behind Section Complete your collection with: The Nebula Secret (1) The Falcon's Feather (2) The Double Helix (3) The Star Dunes (4) The Tiger's Nest (5) Explorer Academy Code-Breaking Adventure Explorer Academy Ultimate Activity Challenge Explorer Academy Field Journal Explorer Academy Future Tech

NOW IN PAPERBACK: An explosive revelation and a familiar face heighten the mystery for Cruz and friends in the sixth book in this adventure-packed series. 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. The paperback edition includes the same great content and back matter as the original hardcover. Explorer Academy features: Gripping fact-based fiction plot that inspires curiosity with new technology and innovations; amazing inventions and gadgets; a cast of diverse, relatable characters; secret clues, codes, and ciphers to track down within the text; vibrant illustrations; elements of STEAM; National Geographic explorer profiles in the Truth Behind section Complete your collection with: The Nebula Secret (1) The Falcon's Feather (2) The Double Helix (3) The Star Dunes (4) The Tiger's Nest (5) Explorer Academy Code-Breaking Adventure Explorer Academy Ultimate Activity Challenge Explorer Academy Field Journal Explorer Academy Future Tech

Adventure, danger, and a thrilling global mission await 12-year-old Cruz Coronado as he joins an elite school for explorers. Cruz leaves his tranquil home in Hawaii to join 23 talented kids from around the globe to train at the Explorer Academy with the world's leading scientists to become the next generation of great explorers. But for Cruz, there's more at stake. No sooner has he arrived at the Academy than he discovers that his family has a mysterious past with the organisation that could jeopardise his future. In the midst of codebreaking and cool classes, new friends and augmented-reality expeditions, Cruz must tackle the biggest question of all: Who is out to get him ... and why? Readers can get in on the excitement with puzzles and codes embedded throughout. With the help of his classmates, Cruz puts together pieces of a complicated puzzle. Suddenly, he finds himself at the centre of an international quest for a missing formula that only he can decode. By the time he boards the Academy's flagship Polaris for his semester at sea, the fate of his friends, and maybe even the world, are in his hands.

The adventure continues as Cruz Coronado and his fellow explorers are jolted from their normal routines at Explorer Academy's classroom-at-sea and thrust into survival mode in the fifth book in the thrilling fiction series. 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 cipher's clues to a magnificent tomb and centre of spirituality precariously perched on the side of a cliff. There, Cruz is confronted by a familliar 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 experiences the ultimate sacrifice and uncovers a hidden message that makes him question his own mortality.