In 1917 the Council of National Defense issued a statement of principles to guide American secondary schools during World War I and added recommendations for adjusting to the rapidly changing economic and social conditions. The document, titled "The War and the Schools," began:

Preamble: In the crisis that confronts us the schools of the Nation should have the single thought to serve their country in the best possible way and in the full extent of their resources, not only in the present emergency but in the years to follow.

Statement of Principles: We accordingly believe, first, that it is of supreme importance that the educational resources of the Nation, and particularly our great public school systems, shall be maintained as fully and completely as possible, in order that our country may not again go thru the sad experiences following the Civil War...