The International Order of the Rainbow for Girls (IORG) is a Masonic

Freemasonry

Freemasonry is a fraternal organisation that arose from obscure origins in the late 16th to early 17th century. Freemasonry now exists in various forms all over the world, with a membership estimated at around six million, including approximately 150,000 under the jurisdictions of the Grand Lodge...

 youth service organization which teaches leadership training through community service. Girls (ages 11–20/21) learn about the value of charity and service through their work and involvement with their annual local and Grand (state or country) service projects.
The order came into existence in 1922,
when the Reverend W.