Margaret Peterson Haddix

In a future where the Population Police enforce the law limiting a family to only two children, Luke has lived all his twelve years in isolation and fear on his family's farm, until another "third" convinces him that the government is wrong.

In a society that allows families to have only two children, third child Matthias joins the Population Police to infiltrate their system.

In a society that allows families to have only two children, a group of third-borns tries to save themselves and others like them. Fifth in the series.

Thirteen-year-old Nina is imprisoned by the Population Police, who give her the option of helping them identify illegal "third-born" children, or facing death.

Told from separate viewpoints, as evil forces from the parallel world invade their home, the Greystones, their doubles, and friends must return to the alternate dimension to save both worlds.

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,...

In a future where the law limits a family to only two children, third-born Luke has been in hiding for the entire twelve years of his life, until he enters boarding school under an assumed name and is forced to face his fears.

When a diphtheria epidemic hits her 1840 village, thirteen-year-old Jessie discovers it is actually a 1995 tourist site under unseen observation by heartless scientists, and it's up to Jessie to escape the village and save the lives of the dying children.

Follows fifth grader Max as he searches for his best friend who disappeared, leaving behind a strange note.

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.