Ruling Destiny by Alyson Noël

The second I stepped through the doors of Gray Wolf Academy, my world disintegrated. Here, time is malleable. It can be manipulated, shifted. Changed. And for those of us who Trip—or travel through time—the possibilities are infinite and perilous.
Now my life is caught in the secrets of everyone around me. Arthur, the eccentric billionaire who rules this school. Killian, who could be the only honest person here…or the biggest liar. And Braxton, magnetic, gorgeous, and unfathomable. The only thing I trust about him is our electric connection.
Whether we’re Tripping through Renaissance Italy or thieving from a ball in Regency England, my life’s become a web of lies and strange truths. And beneath the surface is an elaborate puzzle, filled with cryptic symbols and priceless treasures scattered across history—all somehow connected to my strange ability to see through time.
But Arthur has a dangerously ambitious agenda. And if what my dad taught me is true, I’m not just a threat to everyone at Gray Wolf.
…I’m a threat to time itself.