THE GHOST GIRL

This is the third book of the Protectors of the Wood Series, a six-volume saga about a group of misfit teenagers who save the world from climate change. 
In Book #1, Phoebe arrives back in Middletown after a year away at college. She discovers shocking changes taking place in her familiar childhood home. An immense corporation already owns many local businesses, and is buying up property at an alarming rate. When the local minister preaches a sermon on climate change, an angry crowd walks out in protest. And a valuable gem called dreamstone is attracting extraordinary interest and many unanswered questions. 
Phoebe meets Abby, a mysterious young woman living in an abandoned house on the outside of town. She soon realizes that Abby possesses many secrets, and is hunted ruthlessly by her 
enemies.