Ben Cosgrove, Time, September 28. 2013
Historians and social critics differ on the specifics of the timeline, but most cultural observers agree that the strange and fascinating creature known as the American teenager — as we now understand the species — came into being sometime in the early 1940s. This is not to say that for millennia human beings had somehow passed from childhood to adulthood without enduring the squalls of adolescence. But the modern notion of the teen years as a recognized, quantifiable life stage, complete with its own fashions, behavior, vernacular and arcane rituals, simply did not exist until the post-Depression era.
Here, in the first of a series of galleries on the evolution of LIFE magazine’s — and, by extension, America’s — view of teenagers through the middle part of the 20th century, LIFE.com presents photos that the inimitable Nina Leen shot for a December 1944 article, “Teen-Age Girls: They Live in a Wonderful World of Their Own.”