If you're looking for a problematic, fat-shaming Sweet Valley book, look no further.
Power Play follows Robin Wilson on her quest to become a member of exclusive sorority Pi Beta Alpha. Elizabeth nominates Robin as a potential candidate, but Jessica finds it laughable that someone who is (shock horror) overweight could even contemplate being accepted into such an exclusive group and sets her humiliating initiation challenges whilst leading her on by taking advantage of her good-nature. However, nothing can stop Robin - she's on a mission, and when Liz helps her complete the most difficult task of all - getting Bruce Patman to take her to the dance - Robin is eligible to be put forward for voting. The anonymous voting takes place and Robin is blackballed! The rejection causes Robin to withdraw from school life and, as a result of excessive exercising and minimal eating, lose a lot of weight in a short period of time.
I remember reading this book when I was young and overweight and empathising with Robin, wishing I had the willpower to 'run myself thin' like she did. Robin loses weight and her life improves, because nothing good can ever happen to a fat person in Sweet Valley. This book sends a dangerous message, and I'd go so far as to say this book is at least partly responsible for the issues I've had with my body over the past twenty-five years.
The b plot storyline where Liz suspects Jessica is a common thief stealing scarves and rings from the upmarket store Lisette's is light relief in comparison. When the shoplifter is finally revealed to be Lila, who blames the lack of attention from her father for her light-fingered antics, there are (in true Sweet Valley style) minimal consequences. Seriously, Sweet Valley is corrupt.
It's fair to say Power Play isn't a favourite of mine and I doubt I'll ever reread it again.