This is a fun story about a young girl who has befriended a wild stallion. This was the fourth book in a series, but the only one I've read. It is well written. I recognized that there was background information in the other stories, but the story was self contained enough to stand on its own.
The young girl, Sam, struggles with fairly normal teenage stuff. She struggles with algebra and other school subjects. Sam has to deal with a snotty rich girl who is very self-centered and hardly thinks of anyone else. Sam's family is working hard to keep their ranch.
Connecting all these pieces is Sam's love for a mustang, "The Phantom Stallion." There is a woman in town who supplies animals to rodeos. Sam is worried that the woman may illegally try to capture the wild stallion, and Sam tries to protect the mustang.
This is a good story for young children. One of my daughters found the series and has read every book she could get her hands on, and several of the books she had read more than once. If you have a child who loves horses, this is a good book to get.