Margaret Peterson Haddix

Told from separate viewpoints, Chess, Emma, and Finn Greystone, ages twelve, ten, and eight, investigate why their mother went missing and uncover their ties to an alternate world.

Throughout the hunt for the 39 Clues, Amy and Dan Cahill have uncovered history's greatest mysteries and their family's deadliest secrets. But are they ready to face the truth about the Cahills and the key to their unmatched power? After a whirlwind race that's taken them across five continents, Amy and Dan face the most the difficult challenge yet -- a task no Cahill dared to imagine. When faced with a choice that could change the future of the world,...

Twelve-year-old Zola, who has a surprising connection to Jessie, discovers that she is stuck in a fake utopian future, and that those around her are counting on her to help them escape.

Jonah, Katherine, Chip, and Alex suddenly find themselves in 1483 at the Tower of London, where they discover that Chip and Alex are Prince Edward V and Richard of Shrewsbury, imprisoned by their uncle, King Richard III, but trying to repair history without knowing what is supposed to happen proves challenging. Author's note includes historical facts about the princes and king.

When thirteen-year-olds Jonah and Chip, who are both adopted, learn they were discovered on a plane that appeared out of nowhere, full of babies with no adults on board, they realize that they have uncovered a mystery involving time travel and two opposing forces, each trying to repair the fabric of time.

A twelve-year-old girl raised in a foster village is returned to her biological parents, and discovers home is not what she expected it to be.

A sixteen-year-old boy arranges a housesitting job for the summer, but he starts acting strangely after his family moves in, and his sister begins to suspect they are not supposed to be there.

Jonah, thirteen, and Katherine, eleven, travel through time to 1918 Russia just as Alexei, Anastasia, and the rest of Tsar Nicholas II's family is about to be executed. Author's note includes facts about the Romanov's and the mystery surrounding their deaths.

When Jonah and Katherine travel to early 1900s Switzerland and Serbia to return Albert Einstein's daughter, Lieserl, to history, her mother Mileva grasps entirely too much about time travel and has no intention of letting her daughter go.

In a society that allows families to have only two children, a group of third-borns tries to save itself and others like them. In the aftermath of a crisis that threatens the safety of all shadow children -- illegal third-borns in a society that allows only two children per family -- Trey's friends expect him to take charge -- a function he doesn't want or think he can do. Trey's new role leads him to travel with Luke Garner's brother, Mark, to Population...