In 1951, the newly established Federal Civil Defense Administration (FCDA) commissioned production of a film to instruct children how to react in the event of a nuclear attack. The result was Duck and Cover, a film lasting nine minutes that was shown in schools throughout the United States during the 1950s and beyond. It featured a cartoon character, Bert the Turtle, who "was very alert" and "knew just what to do: duck and cover." At the sound of an alarm or the flash of a brilliant light signaling a nuclear explosion, Bert would instantly tuck his body under his shell. Below, in a photo from November 21,1951, sixth-grade students and their teacher at Public School 152 in the Queens borough of New York City, act out a scene depicted in the film by crouching under or beside their desks.

Other FCDA initiatives of the early 1950s led to creation of the Emergency Broadcast System, food stockpiles, civil defense classes, and public and private bomb shelters. At right, a mother and her children practice running to their steel-walled fallout shelter in the back yard of their Sacramento, California, home on October 5, 1961.

The FCDA commissioned other civil defense films, but Duck and Cover became the most famous of the genre. In 2004, the U.S. Library of Congress included it in the National Film Registry of "culturally, historically or aesthetically" significant motion pictures, a distinction it now shares with such feature-film classics as Birth of a Nation, Casablanca, and Schindler's List.