Born on July 12, 1909, Herbert S. Zim taught at the University of Illinois in the 1950s. It was during his years in Champaign-Urbana that Zim penned or cowrote several of the Golden Nature Guides that taught generations of schoolchildren about stars and planets, American birds and mammals, and dozens of other topics in natural history.

Though a bit dated these days—the Guides predate some rather world-changing breakthroughs in genetics, astrophysics, and humanity’s ability to shoot space probes to Pluto—the books remain accessible, basic introductions to their topics. The New York Times summed it up: “concise, engaging and comprehensible to children without being simplistic.” The text also benefited from attractive illustrations. Indeed the Guides, in particular the early books illustrated by James Gordon Irving, present a jarring contrast to today’s children’s nonfiction, a genre/product dependent on dull photo archives and Legos and whatever can be pulled from Wikipedia for free.

Zim graduated from Columbia in 1933 and taught throughout the 1930s and 1940s. He landed at Illinois in 1950 and taught education for seven years. By then, he already had made a mark writing about mechanical marvels—submarines, zeppelins, and the like—for children. The pocket-sized Golden Nature Guides series, originated by Zim, kicked off in 1949. He also steadily published magazine articles and worked in professional organizations. Meanwhile, across America, children took millions of the Guides on road trips or scouting excursions, picking out the highlights on pond life or watching the trees for a flash of the downy woodpecker.