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

After Susan sees Mr. Smith the substitute teacher peel off his face, she knows he's an alien and only Peter believes her. Together they work to save the class from Mr. Smith's horrible plans.

Man can move easily enough in the three dimensions of space - why not the fourth: Time? An intriguing after-dinner conversation takes an unexpected turn when the host produces a small machine, which promptly disappears into thin air. It has been sent into the future, he says. Or maybe the past. As his skeptical guests try to fathom what they have seen, the host unveils a full-size machine, nearing completion. At a similar gathering one week later...

Shipwrecked on a remote, wild island, Robot Roz learned from the unwelcoming animal inhabitants and adapted to her surroundings--but can she survive the challenges of the civilized world and find her way home to Brightbill and the island? After being captured by the Recons and returned to civilization for reprogramming, Roz is sent to Hilltop Farm where she befriends her owner's family and animals, but pines for her son, Brightbill.

"Life in the community where Jonas lives is idyllic. Designated birthmothers produce newchildren, who are assigned to appropriate family units: one male, one female, to each. Citizens are assigned their partners and their jobs. No one thinks to ask questions. Everyone obeys. The community is a precisely choreographed world without conflict, inequality, divorce, unemployment, injustice--or choice. Everyone is the same. Except Jonas. At the Ceremony...

With the final battle between the Light and the Dark soon approaching, Will sets out on a quest to call for aid. Hidden within the Welsh hills is a magical harp that he must use to wake the Sleepers--six noble riders who have slept for centuries.

Having been judged Different, Norbert, Drew, and Sophie are banished from the United State of Earth to Astro-Nuts Camp on Zorquat 3 in the Orion Nebula, interfering with Norbert's quest to find his parents.

The oceans rose, swallowing the lowlands. Earthquakes shattered the continents, toppling entire regions into the rising water. Now, humans live packed into stack cities. The only ones with any space of their own are those who live on the ocean floor: the Dark Life. When fifteen-year-old Ty, who has always lived on the ocean floor, joins Topside girl Gemma in the frontier's underworld to seek and stop outlaws who threaten his home, they learn that...

Bell has spent his whole life -- all eleven years of it -- on Mars. But he's still just a regular kid-he loves cats, any kind of cake, and is curious about the secrets the adults in the US colony are keeping. Like, why don't they have contact with anyone on the other Mars colonies? Why are they so isolated? When a virus breaks out and the grown-ups all fall ill, Bell and the other children are the only ones who can help. It's up to Bell -- a regular...

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.