How can I lose around 10-15 pounds in about 2 months?

I'm a teenage girl and my class is taking a huge trip to a ski resort at the beginning of April and I want to lose weight so that I can wear a cute bathing suit. I'm not fat but I have some extra jiggle where it shouldn't be especially in my thighs,butt,and stomach. Any suggestions on exercises or diets would be awesome especially if you know of any healthy packed lunches that are easy to make and not too weird because right now I'm at the mercy of the lunch ladies. Any help is appreciated thanks! :)