What's a good way to lose 15-20 pounds?

I'm 14 years old and I really want to lose a bit of weight and get into shape before summer.

You can almost literally hop around for an hour a day and lose weight. Actually, you could. Gte a mini trampoline and jump on it while watching tv. Get a gym membership and run on a treadmill. Join a sports team. Swim every other day. Ride a bike to and from school instead of getting a ride. There's so many easy things to do, it's ridiculous.

a mini-trampoline costed me 18$ at a garage sale and i use it everyday.

Try a detox?
Theres many different varieties on the internet. They usually help you lose water weight and clean out your system.
Theres a very popular one-week diet called "the cabbage soup diet" in which you are supposed to lose 10-20 pounds in just one week!
Also you could try a shake diet. For these you drink shakes (healthy ones) for breakfast, lunch and then you eat a balanced dinner of around 600 cals. This is supposed to make you lose 15 pounds a week. (you can use slimfast shakes, or make your own with fruit and slim milk) Also I've noticed if you put lots of ice in youre shakes theyre a lot bigger and you can sip on them all day without getting hungry (even though youre only adding water)
Biggest suggestion DONT DRINK CALORIES! because you dont think about them. Water, and diet cola and green tea with no sugar is perfect.
And the most important point .... Get moving!! Go for jogs, even do some jumping jacks, every bit counts.
Goodluck to you! Im on the same mission!

whats your weight?

well you could run for 15 min a day
eat a salad for lunch/ snack
do 45 jumping jacks
do 25 sit ups
and 15 push ups

this is my way to work out and i am fourteen and way 100 lbs