I know you want to lose the weight before school starts, but it is completely unrealistic to lose that much weight that fast. Trust me on this, if you set unrealistic goals, you're setting yourself up to fail. Even if you did lose the weight that quickly, you would almost certainly gain it back, if not more. (I did this). I know it's frustrating, but slow weight loss really is best. As for how to lose weight, try going to Dietpower.com, it's a really good program that can help you monitor your eating. It worked for me! :)