The official Girl Scout uniform for girls is a white shirt (either
their own or the official Girl Scout polo shirt for their program
level), their own khaki pants or skirt, and the official program level
tunic, vest, or sash.
Girl Scout Seniors and Ambassadors have an official
neckerchief-style scarf to wear with their uniform, especially when
they are at World Centres, Jamborees, or other events with Guides from
other countries, who typically wear a neckerchief, scarf, or
Girl Scout Senior Sash & Vest.