16th birthday party ideas (girl)?

Okay, so my birthday is in august and I'm turning 16. My first thought was a ballroom with a dj and a bunch of people, but that is so much work and not to mention the cost. So then I thought I'll just have a couple girlfriends over(like 10 including myself), but I don't just want a sleepover. I've read some things on here and I just can't decide on something. I don't want a pool party, we did that when I turned 12. And that was the last real birthday party I had so I really want this one to be as memorable as my 12th. Oh and something not too expensive. I live in Iowa and so it's pretty hot and humid outside during August but I would like it to be outside because I looove the outdoors. I'm not much of a girly girl either. Please help!