The Castle in the Mist by Amy Ephron
This is a story of sister and brother spending their summer vacation in England with an aunt because their father is a journalist in Afghanistan and their mother has cancer. They meet a young boy in a mysterious castle on the top of the hill. Odd things occur. It is all very typical, which isn't always bad as there are always new kids who need to discover books. The problem here is it's not new and it's not executed very well. There is almost no character development and there are a lot of holes in both the plot and the world building. I feel like Ephron got it into her head that writing a children's book would be easy and then didn't bother to read any of the genre to help her know what she was about.
The Gauntlet by Karuna Riazi
The concept of this is Jumanji in reverse-instead of the game coming to life around you, you are part of the game board. The fantastical elements and their origin in Middle Eastern mythos and culture is wonderfully done. The cast of characters is diverse. It is a plot driven, shorter read so perfect for the many many kids who want such books full of adventure and fun. The peril level is low enough that it will appeal to the younger end of the MG spectrum too. On a personal level, I am too much of a character reader to truly love this for myself. I had a lot of questions regarding characterization, particularly many motivations for things that were done. I'm happy to have it for recommendations though!
Prisoner of Ice and Snow by Ruth Lauren
This is a fun, quick MG fantasy read. Valor gets herself arrested and sent to her kingdom's prison for children in order to rescue her twin sister who was arrested for theft of an important object needed by the royal family to complete a peace treaty. In the prison Valor has to learn who to trust and how to survive to complete her plan. This is a plot centric story and moves very fast. As a result, the characterization isn't terribly in depth or surprising, but there is a strong group of young teens working together and forming bonds. I think this works really well as a book to give MG readers who are flirting with fantasy and want to try it out. It is not too long. I was under the impression that this was a stand alone and was really excited to have a MG stand alone fantasy on the shorter side. But alas, the ending clearly sets up a sequel so that isn't the case. Still. It's a good addition to any upper elementary/middle school library.
The Shadow Cipher by Laura Ruby
This is an excellent choice for any and all readers who love puzzles, ciphers, and strategic solving of things. As I am not so much a fan of those, the book took me longer to get through than it normally would. The writing is excellent. Ruby knows how to draw in an audience, develop characters, and create meaningful, layered relationships. All of that was definitely my thing. Theo, Tess, and Jaime are all excellent characters and their friendship along with the relationships with their wider families was well done. The world of New York City Ruby created with its alternate history is a fascinating one. Honestly, that is the book I would rather be reading. The Prologue was so much fun (as was the end). I would read the heck out of that series. I'm going to continue reading this one as well, but there were definitely places where I wished this book were shorter and the pace a bit quicker. But again, I'm not a puzzle person.