The great function of the school, therefore, is to supply the means by which the requisite _knowledge_, _attitude_, and _skill_ can be developed. It is true that the child does not depend on the school alone for his knowledge, his attitude, and his skill. For the school is only one of many influences operating on his life. Much of the most vital knowledge is not taught in the school but picked up outside; a great part of the child's attitude toward life is formed through the relations of the home, the community, and the various other points of contact with society; and much of his skill in doing is developed in a thousand ways without being taught. Yet the fact remains that the school is organized and supported by society to make sure about these things, to see that the child does not lack in knowledge, attitude, or skill. They must not be left to chance; where the educative influences outside the school have not been sufficient, the school must take hold. Its part is to supplement and organize with conscious purpose what the other agencies have accomplished in the education of the child. The ultimate purpose of the school is _to make certain of efficiency_. The means by which the school is to accomplish these ends are (1) the _social organization_ of the school, or the life and activities that go on in the school from day to day; (2) the _curriculum_, or the subject-matter which the child is given to master; and (3) the _instruction_ or the work of the teacher in helping the pupils to master the subject-matter of the curriculum and adjust themselves to the organization of the school. These factors will of necessity differ, however, according to the particular type of school in question. It will therefore be necessary to inquire into the special problem of the rural school before entering into a discussion of the means by which it is to accomplish its aim. _The special problem of the rural school_ Each type of school has not only its general problem which is common to all schools, but also its special problem which makes it different from every other class of schools. The special problem of any type of school grows out of the nature and needs of the community which supports the school. Thus the city school, whose pupils are to live the industrial and social life of an urban community, confronts a different problem from that of a rural school, whose pupils are to live in a farming community. Each type of school must suit its curriculum, its organization, and its instruction to the demands to be met by its pupils. The knowledge taught, the attitudes and tastes developed, and the skill acquired must be related to the life to be lived and the responsibilities to be undertaken.