As young as nine years of age, a child is eagerly inquisitive as to what has taken place in the ages past and readily grasps a concept of World History. Therefore, for many years Calvert School nine-year-old pupils have been taught World History in spite of academic and parental skepticism and antagonism. But I have watched the gradual drift toward adoption of this plan of history teaching, and with it an ever-increasing demand for a text-book of general history for young children. I have found, however, that all existing text-books have to be largely abridged and also supplemented by a running explanation and comment, to make them intelligible to the young child. The recent momentous studies into the native intelligence of children show us what the average child at different ages can understand and what he cannot understand--what dates, figures of speech, vocabulary, generalities, and abstractions he can comprehend and what he cannot comprehend--and in the future all text-books will have to be written with constant regard for these intelligence norms. Otherwise, such texts are very likely to be “over the child’s head.” They will be trying to teach him some things at least that, in the nature of the case, are beyond him. In spite of the fact that the writer has been in constant contact with the child mind for a great many years, he has found that whatever was written in his study had to be revised and rewritten each time after the lesson had been tried out in the class-room. Even though the first writing was in what he considered the simplest language, he has found that each and every word and expression has had to be subjected again and again to this class-room test to determine what meaning is conveyed. The slightest inverted phraseology or possibility of double meaning has oftentimes been misconstrued or found confusing. For instance, the statement that “Rome was _on_ the Tiber River” has quite commonly been taken to mean that the city was literally built _on top_ of the river, and the child has had some sort of fantastic vision of houses built on piles in the river. A child of nine is still very young--he may still believe in Santa Claus--younger in ideas, in vocabulary and in understanding than most adults appreciate--even though they be parents or teachers--and new information can hardly be put too simply. So the topics selected have not always been the most important--but the most important that can be understood and appreciated by a child. Most political, sociological, economic, or religious generalities are beyond a child’s comprehension, no matter how simply told. After all, this History is only a preliminary story.