Two Pearls of Wisdom

The Two Pearls of Wisdom (also known as Eon, Eon: Dragoneye Reborn, or Eon: Rise of the Dragoneye) is a 2008 fantasy novel by Alison Goodman. It follows the story of Eon, who has potential to become a Dragoneye, being able to control wind, water and land. However, Eon is actually a girl concealed as a boy, and with girls forbidden, she becomes a dangerous gamble.