Miranda and Starlight: (Starlight Series: #1) - Janet Muirhead Hill

Miranda Stevens is sure that if she just had a horse of her own it wouldn't matter that she was sent to live with her grandparents and go to a school where she had no friends. She doesn't think twice before taking Christopher Bergman's dare to ride the most beautiful horse she has ever seen. The dire consequence of that action begins a chain of adventure that tests her courage and spawns some unexpected freindships. Both boys and girls will keep turning the pages as they experience a roller coaster ride of adventure and emotion.