Sounds like Keywanettes at my high school. LA had single-sex versions of Key Club for some reason. They made us go co-ed, though
Ours was really hard to get into, though. You had to go to a "party" and answer a random question that you picked out of a basket in front of everyone. Then the members voted on you.
It was a lot of fun. We did service projects and lots of girly stuff, too. Sleepovers, baking cookies, it was a great time!