The Magic of Reason by Justine Larbalestier Book

Reason Cansino isn’t like other 15 year olds. For one thing, she’s spent most of her life in the Australian Outback on the run from grandmother Esmeralda – a real life witch. For another, Reason got her name because her mother, Sarafina, like it better than Logic or Rationality or Intellect – all good words representing the calm, ordered certainty that opposed Esmeralda’s world. Suddenly Magic is real… and Reason is Magic!