Both the Boy Scout and Girl Scout national organizations in the United States encouraged saving for summer camp by their members.  They both printed camp fund stamps that were probably used like savings stamps and were pasted in a savings booklet or folder with the goal of sending a Scout to camp.  Some stamps may have also been used to raise funds for camp construction or maintenance.  Here are a few examples of these stamps:

The set of three labels are in denominations of 5 cents (red), 10 cents (green) and 25 cents (yellow).