And these slimmed-down, simplified and sometimes sanitized editions of popular nonfiction titles are fast becoming a vibrant, growing and lucrative niche.

Image Alternative American history books. Credit... William P. O'Donnell/The New York Times

Publishers are unleashing a flood of these books. Mr. Meacham recently published his first children’s book, a version of his 759-page biography of Thomas Jefferson tailored to readers 10 and older. Atheneum Books for Young Readers will publish a photo-heavy four volume version of Oliver Stone and Peter Kuznick’s controversial and revisionist 750-page book, “The Untold History of the United States,” aimed at fifth to ninth graders. Next month, Mark Kurlansky, who has published illustrated children’s editions of his best-selling nonfiction books “Cod” and “Salt,” is releasing a 10-and-up version of his 2012 biography of Clarence Birdseye, the frozen food pioneer.

It can be hard to maintain the drama and nuance of historical narratives while targeting the under-13 crowd. Mr. Meacham said he had a lengthy debate with his publisher over how to describe Jefferson’s sexual relationship with his slave Sally Hemings. “For a fifth or sixth grader, how do you explain an illicit relationship between master and slave, and be honest, but not send them screaming?” said Mr. Meacham, a Pulitzer Prize-winning biographer. “It’s hard enough to do it for grown-ups.”

“D Day,” a recent children’s title carved out of “The Guns at Last Light,” Mr. Atkinson’s 877-page history of World War II, omits explicit descriptions of the carnage on the Normandy beaches. “Sure, it lost some of its impact,” Mr. Atkinson said of the book, recast for 8 to 12-year-olds. “But that was the point.”

Despite such hurdles, more of these titles are coming next year, including young readers’ editions of “The Boys in the Boat,” Daniel James Brown’s No. 1 best seller about an American rowing team at the 1936 Berlin Olympics; “Far From the Tree,” Andrew Solomon’s lengthy, wrenching study of how families cope with children who suffer from disabilities like deafness, dwarfism, Down syndrome and schizophrenia; and “Quiet,” Susan Cain’s best-selling study of introverts. (While the adult version of “Quiet” focused on challenges introverts face at work and as parents, the children’s edition will feature advice for introverts on how to handle school and extracurricular activities.)