The teacher, then, in dealing with boys, must learn to think in terms of gangs, as well as in terms of individuals. She must, in certain cases, go even further than this and think of gangs entirely, and not of individuals at all. Suppose, for her arithmetic class, she plans to take up as a practical problem, in mensuration and denominate numbers, the material which is, let us say, going into a dwelling-house in process of construction near by. Her thought should not be: I will send ten individuals to measure foundation or cellar or frame, and see which boy comes out best. She should think rather: I will send two gangs of five each, and see which gang comes out best. And these gangs should be as far as possible real gangs. The best device is to select the leaders, who, in turn, one need not say, must be boys whom the rough-and-ready election of their fellows has already elevated to a like post outside. These, then, should select their companions; and at once there results something of the gang structure and spirit. Then the rivalry of the gangs will make each boy expend far more effort than he would ever put forth for his own glory. So it should be with any attempt to accomplish anything for the school. Is the room to be decorated for some occasion? The pupils as a whole should not attend to the room as a whole; nor should the pupils as individuals work as assistants to the teacher. Instead, the work should be divided into parts, and each part should be given to an independent group; to a natural group, as far as possible, but at any rate to a group under a natural leader. Or is it a question of self-government, either in the schoolroom or on the playground? The head monitor, or whatever he is to be called, should pick his own assistants, and be responsible for their results. When the time comes for a change of authority,--it is well to have such change come periodically and somewhat often,--the whole group, prime minister and cabinet together, should go out of office at once, and another group take their place. That is the way men organize their industries and manage their governing. It may often be advisable to have the entire body of pupils elect the successive leaders; but the leader’s assistants who are to work with him should be his own selection. Only thus can one make sure that they “will be in sympathy with the administration”--or, in other words, belong to the same temporary gang.