Here's an excerpt form E.D. Hirsch, Jr's book, The Knowledge Deficit that is pertinent in today's Common Core debate:
"For many years the great reading researcher Jeanne Chall complained that the selections offered in language arts classes did not provide students with the knowledge and language experiences they need for general competence in reading...far too much time was being spent on trivial, ephemeral fictions and far too little on diverse nonfictional genres [e.g. history]... little has changed. Most current programs still assume that language arts is predominantly about “literature,” which is conceived as poems and fictional stories, often trivial ones...Stories are indeed the best vehicles for teaching young children—an idea that was ancient when Plato asserted it in Republic. But stories are not necessarily the same things as ephemeral fictions. Many an excellent story is told about real people and events, and even stories that are fictional take much of their worth from the nonfiction truths about the world that they convey.
"The association of language arts mainly with fiction and poetry is an accident of recent intellectual history that is not inherent in the nature of things. Older American texts that were designed to teach reading, such as the McGuffey Readers, contained moral tales and historical narratives as well as fictional stories (not that we should go back to the McGuffey Readers, which have many shortcomings). Ideally, a good language arts program in the early grades will contain not only fiction and poetry but also narratives about the real worlds of nature and history. Ideally, such a program will fit in with and reinforce a well-planned overall curriculum in history, science, and the arts.