if you have a treadmill that will help if not do crunches push ups and sit ups then squats for a half an hour each day for a month that should help
maybe you should exercise in a pool with your grandma
oh im sorry, i didn't know
alright i got your perfect workout. check this out> http://www.youtube.com/watch?v=3U8pAM4VXvI&feature=player_detailpage
If you must you can even walk in the house, even you have to walk in place, though the most important factor in losing weight is reducing your food intake. I lost a LOT of weight with NO exercise at all, so I KNOW it is possible.
u dont need money u can run on track at a park on the sidewalk or almost anywhere and your school must have a gym so make use of it your parents are paying for it