I need to get thin within the week.?

Ok the thing is my school talent show is coming up next week, the auditions was 2 months ago, and I got picked to be in it. Problem is I gained some weight since then because my grades where slipping and I sat on my butt for a month and a half studying, and nothing else. Day schedule, Get up eat breakfast go to school come home from school have a snack, sit down study, eat dinner, study, go to bed. C no activity. Now that my grades are back up, I realized that I gained weight and the talent show is coming up. ( Oh and in case your wondering, Im doing a very very graceful dance and I dont look so good right now. Oh and I also have a very strange metabolism, I gain weight easily, and It's kinda hard for me to lose weight ). So I found out last week and have been doing nothing but, jog, work out, and wii fit, but Im not losing it fast enough! So if anyone can find a way for me to lose 5 or at least 3 pounds within 7 days, it will be a HUGE help!