umm well.just stay active, don t not try in gym. (gym is actually a good source for exercise) don t stop eating..... it actually makes things work.especially at the age you are at, it wont take that long to loose the weight.you can do it! :) good luck!
Cut out all junk food! Drink plenty of water. Walk at a faster pace between classes. Take a 15-20min run every day...that s not too much time to accomplish what you want. Good luck...don t quit.