You're talking about sororities, right? Not Ford modeling? They want a picture of you that is clear so that they can recognize you later on. They are not judging your style sense or (gasp) that you have a picture from the fall when they will be looking at them in the summer. No cutesy, certainly no slutty. A head shot. And if you're sending in two, a 3/4 or full length shot. Like this
Well, except way younger and hopefully cuter.