The chapters of the famous book The Art of War by Sun Tzu read for the school environment. There are books that you can read (decode the words) at any age and they are good for that. But there are books that besides decoding the words you need to understand their deeper meaning and these books are great and there are books that demand an attitude from you, charge you, do not let you sleep, infuriate your soul, shake the shelves in your head and make the well-organized "room" have to be torn down and put back together again, books that make us see truths we do not want to see, accept premises that we insist on denying, in short, readings that require us to position ourselves before them and for them. These are the essential readings. Sun Tzu's The Art of War is a small/large book about tactics to accomplish a certain strategy, that is, the sensitivity and perception of establishing a goal (strategy) and, after that, the science/art of choosing the most efficient and effective methods (in our semantic field: didactics).