I sincerely doubt that. Large percentages of Americans never went past grade school in those days. And many only had a few years of schooling. I would guess a lot of people had the rudiments of reading and writing, but many most likely never read a book other than the bible after they got out of school. And I doubt many of them read the bible much. By 1940, only fifty percent of Americans had graduated from high school.
Reading accounts of major league baseball players from those days, many were semi-illiterate farm boys who liked saloons, drinking, and loose women a lot more than libraries and going to the opera. They were probably typical of many of the adults from that era.
-— By 1940, only fifty percent of Americans had graduated from high school. -—
True. Kids today spend much more time in school. Are they smarter? Wiser? More moral?
Schooling and learning aren’t synonymous but, more often than not, antithetical.
You are applying standards of today to the past. My father dropped out of school in the tenth grade ca. 1930. He would be embarrassed by his MBA grand daughter’s (My niece) lack of English and math skills. You can’t compare grade levels of the past to today. 6th grade tests from the 20s and 30s are too challenging for college students of today.