I read William Sleator's books (particularly Interstellar Pig and Singularity) when I was a kid, and the mix of horror and science fiction was a hit with me, so I was excited to read this new book, The Phantom Limb. The story was compelling, but not so creepy as I remembered the other books being, so this might be good for 3rd or 4th grade and up. In the preview copy I read, it was difficult to tell whether Dr. Ciano was a man or a woman, and that was a bit confusing. The name DCynthia was annoying to read. Having a section in the back of the book that included a few of the optical illusions mentioned in the book would probably be a hit with the kids. Overall, I'd recommend this to average readers in 4th and 5th grade, and middle school students who were a little behind.