This weekend, thousands of twins will descend upon the town of Twinsburg, Ohio, for the 40th annual Twins Days, the largest gathering of twins and other multiples in the world. Twins have long been a source of curiosity to non-twins—who wonder what classes they might have gotten away with skipping had they had an identical stand-in—as well as to scientists, who study twins to better understand the genetic versus environmental origins of certain traits.
When LIFE photographed 17-year-old identical twins Betty and Barbara Bounds in 1947, the magazine was more concerned with what the Bounds sisters had to say about the life of the postwar American teenager than that of a twin. Photographer Nina Leen captured the lives of the Bounds’ teenaged cohort in Tulsa, Okla., from their hairstyles (they “wear it shoulder-length”) to their accessories (“combs are often carried in sock”) to their interests (“boys and parties”).
Liz Ronk, who edited this gallery, is the Photo Editor for LIFE.com. Follow her on Twitter @lizabethronk.