Rosie Frost and the Falcon Queen by Geri Halliwell-Horner

A sweeping adventure filled with a hidden island, family secrets, shocking betrayals, amazing music, and girl power, by iconic Spice Girl, songwriter and author Geri Halliwell-Horner.
It's time to find your power.
Suddenly orphaned and alone, Rosie Frost is sent to the mysterious Bloodstone Island—home not only to a school for extraordinary teens, but also a sanctuary for endangered species. There, Rosie confronts a menacing deputy headmaster, a group of mean girls intent on destroying her, and shocking family secrets. She also discovers that history can come to life in ways she never could have imagined.
When the island itself comes under threat, Rosie knows she must enter and win the Falcon Queen Games in a desperate bid to save it.
But Rosie can't do it alone. She finds that believing in herself—and her friends—is the first step to finding the power she never knew she had.