The use of sandboxes began in the 1840s in Germany. The early developers of the concept of kindergarten were actually pioneers in child psychology! Astutely observant, they probably noticed the natural play of children on the beach and felt the need to recreate this in all spaces. In the United States, in the 1920s, with the rise of behavioral psychology, they saw the immediate benefits of implementing the use of sandboxes in society throughout America, too.