I am a high school math teacher, and I think this book is amazing. I waffled about buying it, since I have read all of Liljedahl's research papers and followed the thinking classroom movement for years, and had implemented many of his suggestions. Would it really be worth it? Would I learn anything new? The answer is definitely YES.  Each chapter is focused on a particular classroom practice, and Liljedahl briefly shares his reasearch process (many, many classroom implementations, and lots of student interviews) and results. Then he shares the specific moves that worked best according to his research. Each chapter has a FAQ section, which usually includes exactly the skeptical questions I would have asked, along with reasonable, specific answers. There is a TON of very clear advice in this book, actionable advice that doesn't require a lot of money or equipment to implement. It DOES require a willingness to try some new approaches for long enough to see results. I've been doing this for four years, and am only growing more convinced that what Liljedahl discovered in his research works in my classrooms as well. I'm reading this book during the summer, and it's getting me excited for next year, and I see solutions to a few of my teaching difficulties.