The Named (Guardians of Time #1)

Ethan is a member of the Named, sworn to fight the Order of Chaos, an evil group determined to permanently change the course of history. But he is also a normal high school student trying desperately to keep up with his homework and fit in. When he is assigned to mentor Isabel, a cute classmate and future member of the Named, the line between his two lives begins to blur. So begins an epic quest as Ethan, Isabel, and others travel through time to battle dark forces and protect the future.