Cals?

Does anyone know where do teens go to get neccesary cals?

Any calculators

This site is specifically aimed at the under 21s.  http://www.bcm.edu/cnrc/bodycomp/bmiz2.html   Enter your stats and read off the numbers that most accurately reflect how active you are to get your maintenance calorie intake. 

Is that righ

I think it overestimates or

Not?

Why not give it a go?

I've heard that many teens on CC have used it successfully.

It's a pretty good indicator of energy (calorie) needs and if you're getting the right energy you're more likely to get the right level of nutrition at the same time.  If you're training for a marathon (as per your blog) you're definitely in the very active category and you may even need to increase on that.