Dark Moon Gates: Witches' Gates Saga Book 1
Willa, witch and H.S. Junior doesn't yet know that the substitutes infiltrating her school are Faery Sidhe in disguise. Or that they plan to sacrifice her baby brother to seal the Gates between the humans and Faery forever. She has two weeks--until the Dark Moon--to save him. If she fails, the human world will perish from lack of magic. If she succeeds, a prophecy says she will be struck blind.