One of the most significant recent developments in the field of the teaching of science has been the refining and defining of major objectives. Departing from earlier precedents, the Society's Committee on the Teaching of Science announced only two great objectives of all courses in science at the elementary and secondary levels: (1) to give a functional understanding of major generalizations or principles, and (2) to inculcate scientific attitudes. Subject matter, which is of course admitted to be essential as the basis of every course in science at every level, is considered by this Committee not as an end in itself but as a means to more important ends.

Educational research, in the modern sense of the term, was first applied to problems in the teaching of science a little more than twenty years ago. During the period since the publication of the results of these pioneer efforts there has been a large and rapidly increasing number of investigations of a wide variety of problems touching many phases of science teaching.

In the best modern schools, laboratory work and the various other activities of the science classroom are frequently carried on in the same room, and together they constitute a carefully integrated whole. The materials briefly presented in this chapter should therefore be considered as a continuation of those in Chapter VI. They have been grouped separately here for the sake of securing perhaps a clearer and more unified treatment of related groups of problems. The discussions, nevertheless, cover so wide a variety of problems, so diverse in nature as to make impossible a logical order of sequence.

During the past quarter century several factors have operated in modifying instructional materials in science, especially those for the secondary school. Prominent among these influences are (1) the 'high-school movement,' which, beginning about 1892, brought into the sec- ondary schools enormously increasing numbers of pupils, and therefore reduced to a marked extent the degree of selection; (2) a resulting diminished emphasis upon the college-preparatory aim, which combined with other factors to render progressiyely less satisfactory and less appropriate the earlier type of textbook that comprised merely a somewhat simplified revision of materials written by university teachers for college and university classes; (3) important trends in educational psychology, prominent among which were a discrediting of the current extreme theories of general transfer and discipline and of serial and saltatory development and a growing acceptance of the functional point of view and of the theory of gradual and concomitant development; and (4) the beginnings of modern educational research, which has been contributing findings of increasing scope and refinement.

The curriculum of science, as well as the materials for the courses that make up the curriculum, must be determined on one of three bases: (1) best opinion regarding what sequence of courses should comprise the curriculum and what elements should make up these courses; (2) the results of such researches as shed light upon these questions; and (3) a combination of opinion and the results of research.