" The main vehicle for nineteenth-century socialization was the leading textbook used in elementary school. They were so widely used that sections in them became part of the national language. Theodore Roosevelt, scion of an elite New York family, schooled by private tutors, had been raised on the same textbooks as the children of Ohio farmers, Chicago tradesman, and New England fishermen. If you want to know what constituted being a good American from the mid-nineteenth century to World War I, spend a few hours browsing through the sections in the McGuffey Readers. "

― Charles Murray , Coming Apart: The State of White America, 1960-2010