The Lightning Thief: Percy Jackson and the Olympians: Book 1 (Unabridged) - Rick Riordan
Twelve-year-old Percy Jackson is about to be kicked out of boarding school . . . again. No matter how hard he tries, he can't seem to stay out of trouble. But can he really be expected to stand by and watch while a bully picks on his scrawny best friend? Or not defend himself against his pre-algebra teacher when she turns into a monster and tries to kill him? Of course, no one believes Percy about the monster incident; he's not even sure he believes himself.
Until the Minotaur chases him to summer camp.
Suddenly, mythical creatures seem to be walking straight out of the pages of Percy's Greek mythology textbook and into his life. The gods of Mount Olympus, he's coming to realize, are very much alive in the twenty-first century. And worse, he's angered a few of them: Zeus's master lightning bolt has been stolen, and Percy is the prime suspect.
Now Percy has just ten days to find and return Zeus's stolen property, and bring peace to a warring Mount Olympus. On a daring road trip from their summer camp in New York to the gates of the Underworld in Los Angeles, Percy and his friends–one a satyr and the other the demigod daughter of Athena–will face a host of enemies determined to stop them. To succeed on his quest, Percy will have to do more than catch the true thief: he must come to terms with the father who abandoned him; solve the riddle of the Oracle, which warns him of failure and betrayal by a friend; and unravel a treachery more powerful than the gods themselves.