The series takes place over a short time frame, with Pony Club Cup taking place in the Easter summer holidays, and Pony Club Trek in the summer holidays. It's not particularly realistic to expect that there will be major changes in character and behaviour in that short a time, and there aren't. I must admit that I did long, when I read the book, for the ghastly Sarah and her even more ghastly mother, Mrs Rooke to well and truly get their come uppance, but they don't: Sarah does though become the victim of her character flaws, not improving at all as she refuses to listen to anyone's opinion but her own.
I do know that Josephine Pullein-Thompson did base many of her characters on real people. The hideous Pony Club mother that is Mrs Rooke has many equivalents in real life, so I hope that the fictional Mrs Rooke is a composite and has no real life equivalent, and that Sarah doesn't either. She must have become a monster.
In a book full of richly drawn characters, it's odd that there's no Major Holbrooke equivalent. He was an irascible, confident and knowledgeable voice throughout the Noel and Henry series, who we saw as a person with a life outside the Pony Club. We know as little about David the instructor at the end as we do at the beginning.
If you haven't read the Woodbury series, I can highly recommend it. The books were published in paperback, and then in a collected edition in hardback, and all are easy to find.
The Woodbury Pony Club SeriesPony Club Cup
Pony Club Challenge
Pony Club Trek
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