Not everything is as it appears when dragons and magic is involved. Twelve-year-old Eon has been training for years. He hopes to be chosen as a Dragoneye — an apprentice to an energy dragon of good fortune. But Eon has a deadly secret. Eon is actually Eona, a sixteen-year-old girl, pretending to be a boy. Girls are forbidden from using Dragon Magic. If anyone learns her secret she, and everyone who helped her, will be killed. When her secret is threatened she is plunged into grave danger and a deadly struggle for the Imperial throne.

You can find this book in the Young Adult Fiction section under Goodman.