☛ National Archives: 4-H Club Members with Chart, “This Dairy Product Has Merit” , ca. 1950, photographic print created by the Department of Agriculture’s Extension Service. National Archives Identifier: 5725634. Local Identifier: 33-A-90-1. Public domain.

This photograph is part of the “4-H Photographic Subject Files, 1923 – ca. 1990”:

This series consists of photographs documenting the history of the 4-H program. Subjects include meetings, ceremonies, exhibits, recreation and projects, including those relating to animals, clothing, community improvement, crafts, conservation, food, gardening, home improvement, forestry and safety. There are also photographs of 4-H Corn Club projects.

The two young women are wearing hats displaying the 4-H logo (a four-leaf clover with a capital letter “H” on each one of them):

4-H in the United States is a youth organization administered by the National Institute of Food and Agriculture of the United States Department of Agriculture (USDA), with the mission of “engaging youth to reach their fullest potential while advancing the field of youth development.” (Wikipedia; see also the official 4-H website)

Only two items of this series are available online at the National Archives (including the one shown above).
This photograph is featured as part of a new exhibition held by the National Archives titled “What’s Cooking Uncle Sam?” running from June 2011 to January 2012. The exhibition explores the history of the relationship between government agenda and food habits in the United-States:

We demand that our Government ensure that it is safe, cheap, and abundant. In response, Government has been a factor in the production, regulation, research, innovation, and economics of our food supply. It has also attempted, with varying success, to change the eating habits of Americans.
From the farm to the dinner table, explore the records of the National Archives that trace the Government’s effect on what Americans eat.

A preview of the exhibition is available online. For a more detailed presentation, read the official press release (March 1st, 2011)