This is what we found on Wikipedia regarding the Girl Scout:

Girl Guides (known as Girl Scouts in the United States and some other countries) is a worldwide movement, originally and largely still designed for girls and women only. The movement began in 1909, when girls requested to join the then-grassroots Boy Scout Movement.

The movement developed in diverse ways in a variety of places around the world. In some places, girls joined or attempted to join preexisting Scouting organizations. In other places, all girl groups were started independently; some would later open up to boys, while others merged with boys' organizations. In other cases, mixed-sex groups were formed, some of which sometimes later disbanded. In the same way, the name "Girl Guide" or "Girl Scout" has been used by a variety of groups across different times and places.

The World Association of Girl Guides and Girl Scouts (WAGGGS) was formed in 1928 and has member organisations in 145 countries. WAGGGS celebrated the centenary of the international Girl Guiding and Girl Scouting Movement over three years, from 2010 to 2012.