You should really talk to your parents about this, but I didnt like having that "talk" this past yr either. ;) So I'll help you out. :) You'll grow taller, your shoulders will become broader, your voice will change (become higher first then deeper), you'll sweat more, and grow hair, and uh.. your penis gets bigger down there. also you will want to have sex with girls. When you want to have sex with them you penis will get straight and hard and it will rise. ;) Hope that helps.