Princess Takes Academy by Joely Sue Burkhart

Our favorite unicorn princess is growing up.
THE COMPLETE PRINCESS TAKES UNICORNS PREQUEL

Xochitl can’t wait for her unicorns! Queen Shara Isador promised she could have unicorns as Blood and even called her Princess of Unicorns. How long will Xochitl have to wait before her Blood come to her call? And will they actually be flying unicorns… or does the Great One have other plans?
PRINCESS TAKES ACADEMY, PART ONE
Now seventeen years old, Xochitl is ready to gain her independence and leave the Zaniyah nest. A devastating mistake nearly five years ago cost her everything—her power, her best friend and Blood, Keras, and very nearly her life. Her family sent Keras away to the Academy of Blood as punishment, and without her Blood, she fears she’ll never regain her power. But before she can leave her family’s house, she must gain permission from the Triskeles queen, Shara Isador.
Unfortunately, the last time the queen saw her, Xochitl swore to never speak to her again.
She’ll lie, cheat, steal, and certainly break the rules again, whatever it takes to get to Keras. He’s the answer to regaining her power. She’s sure of it. Surely she can follow the rules long enough to get to him.
But if there’s ever trouble to be found, Xochitl will be at the heart of it.