The Zero Equation — Christopher G. Nuttall

Caitlyn Aguirre is no magician ...... But she's still at the centre of the storm.Caitlyn and her friends have returned to Jude's Sorcerous Academy, but all is not well in the school.  The Great Houses of Shallot are on the verge of going to war and the conflict is spilling into the school, while - in the background - powerful and secretive forces prepare to finally reveal their plans to reshape the world.  Caught in the middle, torn between her family and her friends - and burdened with a secret she dares not share - Cat must unlock the secret of the Zero Equation ...... Or watch helplessly as her family, friends and school are destroyed by war.