The Aurora Cycle Series 3 Books Set by Amie Kaufman and Jay Kristoff (Aurora's End, Aurora Rising, Aurora Burning)

Aurora Rising

The year is 2380, and the graduating cadets of Aurora Academy are being assigned their first missions. Star pupil Tyler Jones is ready to recruit the squad of his dreams, but his own boneheaded heroism sees him stuck with the dregs nobody else in the Academy would touch

Aurora Burning

First, the bad news: an ancient evil--you know, your standard consume-all-life-in-the-galaxy deal--is about to be unleashed. The good news? Squad 312 is standing by to save the day. They've just got to take care of a few small distractions first. Like the clan of gremps who'd like to rearrange their favorite face.

Aurora's End

Is this the end? What happens when you ask a bunch of losers, discipline cases and misfits to save the galaxy from an ancient evil? The ancient evil wins, of course.