The most promising of the classmates, Donald Beatty, lived in an integrated neighborhood in Columbus, Ohio, where he had a highly desirable job as a supervisor at a state agency and where Parks’s pictures show him — very much in the vernacular of Life magazine’s Eisenhower-era domestic scenes — happy and secure with his wife and toddler son and a brand-new Buick. But notes made by a Life fact-checker just a year later, when the magazine planned once again to run Parks’s article, recorded a tragedy, blithely and with no explanation: “Aside from the death of their son, nothing much has happened to them.”

Lorraine Madway, curator of Wichita State University’s special collections, said of the Fort Scott story: “There are those moments in an archive when you know you’ve found the gold, and this is one of them. It’s a wonderful example of micro-history. It’s not only that there is so much material written at a specific time in people’s lives, but then there are Parks’s reflections on it later.”

Since its formation in 2007, a year after Parks’s death at 93, the Gordon Parks Foundation has collaborated with three museums — the Studio Museum in Harlem, the New Orleans Museum of Art and the High Museum in Atlanta — to organize small, highly focused exhibitions that delve into single bodies of Life magazine work, much of it not seen in years. (All but a few of the 42 photographs in “Gordon Parks: Back to Fort Scott,” the show at the Museum of Fine Arts, have never been published or exhibited before.)

Ms. Haas approached Peter W. Kunhardt Jr., the foundation’s executive director, after following the historical thread of a Parks picture in the Museum of Fine Arts collection showing a young black couple on a date, standing outside a segregated movie theater. Ms. Haas had never known when or where the picture was taken — Parks used it later in his career without identifying it as part of an unpublished Life article. After discovering that the picture showed the Liberty Theater in his hometown, Ms. Haas became intrigued, and with help from the Gordon Parks Museum at Fort Scott Community College, began to dig deeper in the archives, a journey that eventually led her back to Fort Scott, now a town of 8,000.

“Gordon was very disappointed that the story never ran,” said Mr. Kunhardt, whose grandfather, Philip B. Kunhardt was an editor and close friend of Parks’s at Life. “He was really going back to a place that meant everything to him, and he wanted to use it to say something important.”

Besides fact-checking notes, Parks’s own notes and a typewritten draft for what might have been his introduction to the photo spread, there is almost no other documentation surrounding the project, for which Parks shot about 30 rolls of 35-millimeter and medium-format film. And so the question of why it was not published might never be answered. In an essay for the show’s catalog, Ms. Haas speculates that it might have been doomed by its very newsworthiness, as national challenges to school segregation began gathering speed and Life waited — in the end too long — for just the right moment.