The book talks about the main rewards and, on the other side, the main difficulties of being a teacher, about the essentials of good teaching and some great teachers and their pupils, among other things.
I'm not going to give a longer introduction. I think it would be better to just leave you with some quotes/paragraphs that I liked from the book.
"One of the chief duties of a teacher is to stimulate."
"A teacher must believe in the value and interest of his subject as a doctor believes in health."
"Leisure is one of the greatest rewards of being a teacher."
"The teacher's second reward is that he is using his mind on valuable subjects. All over the world people are spending their lives either on doing jobs where the mind must be kept numb all day, or else on highly rewarded activities which are tedious or frivolous. One can get accustomed to operating an adding-machine for five and a half days a week, or to writing advertisements to persuade the public that one brand of cigarettes is better than another. Yet no one would do either of these things for its own sake. Only the money makes them tolerable."
"The third reward of teaching is very closely linked. That is the happiness of making something. When the pupils come to you, their minds are only half-formed, full of blank spaces and vague notions and over-simplifications. You do not merely insert a lot of facts, if you teach them properly. It is not like injecting 500 cc. of serum, or administering a year's dose of vitamins. You take the living mind, and mold it. It resists sometimes. It may lie passive and apparently refuse to accept any imprint. Sometimes it takes the mold too easily, and then seems to melt again ad become featureless. But often it comes into firmer shape as you work, and gives you the incomparable happiness of helping to create a human being."
"He (the teacher) must know the subject. It is not enough for a chemistry teacher to know just that amount of chemistry which is taught in schools and required for the final examinations. He must really understand the science of chemistry. Its upper regions must be clear to him, at least in outline; and he should know what are the most important new discoveries made every year. If a boy shows a gift for chemistry, the master must be able to encourage him, by throwing open window after window into the future, showing him what he can learn at the university, what types of chemistry are most vital in peace and war, which big problems still remain to be solved, and (this is always important) how the great chemists of the past and present have lived and worked."
"Teaching is inseparable from learning."
"One cannot understand even the rudiments of an important subject without knowing its higher levels - at least, not well enough to teach it."
"A limited field of material stirs very few imaginations. It can be learnt off by heart, but seldom creatively understood and never loved."
"It is terribly important when a teacher, whose job is to awaken young minds to a valuable subject, shows his pupils by every gesture, by every intonation of his voice (and remember, young people notice such things very quickly and sensitively), that he thinks the subject is not worth while learning; and that learning anything whatever is a waste of time."
"The second essential is that he must like it." "To be a history teacher and be bored by history, to teach French and never open a French book at home, that must be either a constant pain or a numbing narcosis."
"The third essential of good teaching is to like the pupils. If you do not actually like boys and girls, or young men and young women, give up teaching."
"Unless he likes groups of young people, he will not teach them well. It will be useless for him to wish that there were only two or three, or that they were all mature. They will always be young, and there will always be lots of them."
"You must not be the policeman watching the mob. You must be the leader of a group - something higher than the actor with his audience, something lower than the priest with his congregation, something kindlier than the officer with his unit."
"He must know the names and faces of his pupils. Some people find this easy, some very difficult, but it is a must." "because he would put what felt like really personal venom and vitality into correcting their blunders, and would pass them on the street next day."
"It is a crime to starve a growing talent, but many teachers, out of sheer idleness, commit it every year."
"The good teacher is a man or woman of exceptionally wide and lively intellectual interests."
"Teachers in schools and colleges must see more, think more, and understand more than the average man and woman of the society in which they live."
"They must know more about the world, have wider interests, keep a more active enthusiasm for the problems of the mind and the inexhaustible pleasures of art"
"The good teacher is an interesting man or woman. As such, he or she will make the work interesting for the students, in just the same way as he or she talks interestingly and writes an interesting letter."
"One of the most important qualities of a good teacher is humor. Many are the purposes it serves. The most obvious one is that it keeps the pupils alive and attentive because they are never quite sure what is coming next."
"the wise teacher will continue to introduce flashes of humor extraneously, because he knows that fifty-five minutes of work plus five minutes of laughter are worth twice as much as sixty minutes of unvaried work."
"A very wise old teacher once said: I consider a day's teaching is wasted if we do not all have one hearty laugh."
"We said that one function of the teacher was to make a bridge between youth and maturity. If he has a sense of humor, he can build the bridge."
"Togetherness is the essence of teaching."
"Memory, then, and will power are two of the qualities that make a good teacher. The third is kindness. It is very difficult to teach anything without kindness." "The pupils should feel the the teacher wants to help them, wants them to improve, is interested in their growth, is sorry for their mistakes and pleased by their successes and sympathetic with their inadequacies. Learning anything worth while is difficult. Some people find it painful. Everyone find it tiring. Few things will diminish the difficulty, the pain, and the fatigue like the kindness of a good teacher."
"Ask anyone outside of the profession what he thinks are the principal defects of teachers. He will give you two. One is impractically, "being too academic". The other is repetition, "teaching the same old stuff year after year." The second fault is far worse than the first, and will be avoided at all costs by every good teacher."