"The Common Core dictates that by fourth grade, public school students devote half of their reading time in class to historical documents, scientific tracts, maps and other “informational texts” — like recipes and train schedules. Per the guidelines, 70 percent of the 12th grade curriculum will consist of nonfiction titles."
What Tom Wolfe once said about New Journalism could be applied to most student writing. It benefits from intense reporting, immersion in a subject, imaginative scene setting, dialogue and telling details.
In my opinion, students need to read quality nonfiction and fiction texts across a variety of genre including historical and narrative non fiction in order to learn how the genre works. However, students need to be empowered to READ the genres they love in order to have to fluency, comprehension and confidence to take on any text they are handed on a random Monday morning in the spring!