THE ELEMENTARY-SCHOOL CURRICULUM 151
ences, which form the social setting for the child's constructive activities, constitute the history of this period.
Constructive activity is also the means of acquiring an expe- rience which is the foundation of the sciences and arts. The science of the child is but one phase of his constructive activity. This activity requires that the child of seven years exploit his environment in the search of raw materials which he requires for his constructive work ; that he experiment with them until he finds a way of rendering obstinate materials more pliable, and crooked ones straight ; that he invent tools and devices of various kinds by means of which he can economize his own energy, or apply a motive power other than that of his own muscles ; that he exploit his own neighborhood with reference to the fitness of different localities to supply the needs of the various hunting, fishing, pastoral, agricultural, mining, or trading people that he may be interested in at the time. Such activities as these bring the child into close contact with the earth as the source of supply and enable him to gain control over his own powers. Thus the way is paved for a more intelligent control over the materials and forces of his natural environment.
The child's spontaneous art activities, as well as his interest in art products, indicate that there is much in the art of primi- tive peoples that is necessary in order to pave the way to an appreciation of the higher art forms. In fact, each subject of the curriculum finds the germ of its development in the life of primitive peoples. When this fact is more generally recognized, when all subjects of the curriculum are developed naturally, it will be possible for the child to translate the subject-matter into terms of his own practical activities. This is the essential con- dition in order to secure a unified curriculum. When subjects are presented that are too far beyond the reach of the child to become a part of his experience, when he is obliged to use words that have little significance to him, the search for a uni- fying principle must be in vain.
The question of organizing constructive activities so as to present well-graded steps in the evolution of technique is a fundamental one. It is not at all strange that many teachers
