Green Rider by Kristen Britain
Totally disgraced after her expulsion from school, Karigan trudged homeward through the countryside. It wasn't an easy walk, more of a cross-country hike, really, but her shame and rage kept her moving even as she spent an aching night sleeping in a meadow and washed down some hunks of cheese and bread with less than clean brook water.
Suddenly from out of the dark woods, there came an explosion of red and green.