Finding your caloric intake depends on what activities you do, your age, your weight, your height, and your gender. For teenage girls 11-18 years old, the average amount of calories they should eat per day is about 2200calories. For teenage boys 11-18 years old, the average amount of calories they should intake per day is about 2500-3000calories. (Roxy)
http://www.exercise4weightloss.com/teen-calorie-intake.html
http://www.weightloss-center.net/calorie-needsteens.htm
http://kidshealth.org/teen/food_fitness/sports/eatnrun.html