This entertaining activity book would be a good resource for the middle school math, ELA, or gifted teacher. The book is meant to be used over a fourteen day period to "train the brain" to become stronger and more agile through the use of these critical thinking puzzles. Each day has an activity in each of the following categories: memory, words, numbers, logic, and pictures. Answers as well as scoring rubrics are available in the back of the book, as well as a log for students to keep track of their progress. I was disappointed in the fact that there was no scale to describe the student's level of success. The tracker is meant for the students to see their improvement, but I feel that students at this age level may want a more tangible description of their accomplishments, and may not appreciate simply that their daily score may begin to rise after a few days. Another element of the format of the book is that a joke or riddle is included at the bottom of most pages; even this contributes to the "brain training" of the book, as many of them rely heavily on puns, which requires a certain amount of critical thinking and understanding of the concept in context to get the joke. As a math teacher, I was frustrated sometimes when key information is given away as a "hint", although I understand that this is probably done to be able to reach a wider range of readers. I enjoyed the illustrations, as they often had something to do with one of the answers--perhaps a subliminal message on the part of the authors? One final comment about the book would be that I feel that it could have increased in difficulty more as the days progressed. There were some elements of this, but I found the puzzles began to become a bit repetitive. Overall, I think this is a useful resource for the classroom, and I would definitely love to have a copy for my own to use in my Daily Challenge Problem for my students. ( )