I couldn’t find this online all in one place except for a PDF from the San Diego council, so this is shamelessly borrowed from them. I added the graphics.
Choosing a Troop Crest
In the early days of Girl Scouting, troop crests were used to identify a troop. The rapid growth of the movement soon made numbering necessary, but troop crests were kept as a symbol of a troop’s goal or main interest. Today, troops should think carefully about the crest they choose. It should have a special meaning to them, one they can pass along to new members each year. The symbol can be used on a troop flag or to mark troop equipment. Every member should know what their crest is and what it means. Read more »