In these colorful images, Chicago kids participating in a Wildflower Preservation Society event around 1920 show off their flower costumes.
The Wildflower Preservation Society, founded in 1902 at the New York Botanical Garden, worked to promote love of flowers and of nature through preserving tracts of land and planning educational events. In the Progressive Era, as the population rapidly urbanized, many similar conservation groups popped up, and many of them prioritized the nature education of city children as a major goal. Events like this wildflower pageant were meant to teach urban kids to enjoy the plants that were increasingly absent from their daily lives.
These images are digital scans of hand-painted glass lantern slides, which could be projected so that an audience could view them. The Wildflower Preservation Society may have used these images at their public events as a promotional tool, intermixing them with pictures of flowers and gardens.
The full set of images from this event can be found on the Field Museum Library's Flickr page.