"What would you do if you had a time machine that took you hundreds or thousands of years into the past . . . and then broke? How would you survive? Could you improve on civilization's original timeline? And how hard would it be to domesticate a giant wombat? In How to Invent Everything, bestselling author and time-travel enthusiast Ryan North answers all these questions so you don't have to. This guide contains all the science, engineering, mathematics,...

What if every time you made a choice that had a significant consequence, a new, alternate reality was created--the life that would've been? What if those new Realities were in danger? What if it were up to you to save all the realities--and in turn, the entire universe? Atticus Higginbottom, a.k.a. Tick, was living a regular life until the day a strange letter arrived in his mailbox. Postmarked from Alaska and cryptically signed with the initials...

"When something crucial goes missing, eleven-year-old Olive and her friends must decide how to get it back--put their faith in a strange and dangerous magic, their odd new neighbors, or someone more uncertain and terrifying than both"--

When a motley crew of college scientists discovers the secret to time travel, they quickly come to realize they've bitten off more than they can chew.

A deeply fascinating, engaging, and highly accessible explanation of Einstein's equation, using everyday life to explore the principles of physics.

When Kit Livingstone learns that Britain's "ley lines" are not legends but pathways to other worlds, he's determined to find a map tattooed on a piece of skin in order to travel to the dangerous realms. But are the intricate codes more than they seem--can they really begin a quest to regain paradise?

The present day and an alternate future merge as a child is kidnapped, a writer reaches into the past to discover the truth about a possible murder, and a young woman prepares for her mysterious future.

With Saint Dane seemingly on the verge of toppling all of the territories, Pendragon and Courtney set out to rescue Mark and find themselves traveling--and battling--their way through different worlds as they try to save all of Halla.

With their house in foreclosure, sisters India and Mouse and brother Finn are sent to stay with an uncle in Colorado until their mother can join them, but when the plane lands, the children are welcomed by cheering crowds to a strange place where each of them has a perfect house and a clock that is ticking down the time.