The Boy Who Reversed Himself
First Imagint a 2-d world; like on a sheet of paper. If someone from 2-d world wants to get over a "wall" he can just go over it in 3d world. But, when a couple of teenagers get lost in 4d world, things start to go wrong!
In this sci-fi classic, Laura gets a couple mysterious notes in school, in mirror writing. Later, she realises that a boy at her school, Omar, had been leaving them as he saw that his face had been reversed, as in a mirror. She convinces him to tell him her secret, and he tells her about the Fourth Dimention, and how he'd been using it to sneak things into her locker. He also teaches her how to go into the fourth dimention; but when Laura and her boyfriend get lost there, there isn't much Omar can do to save them. Watch as they struggle to get home, and return to the right dimention!