The Elemental book

In a high school of a million teens, five teens who mystically find a magical book in a library will be called the ELEMENTALS.
They are the 8 elements two evil and six protect the book from dark forces, they are teleported into the book to save a former protector of the book, Thomas Lynn a famous boy who disappeared in 1994, Who's sister is an element of darkness a witch whom trapped him in the book, for a dozen years.
They must find their gemstone to unlock their inner power. The witch is now an element of lightning and is against the darkness. They will earn the right to be Guardians one day, but for now they remain in the elemental academy to control their emotions and power.