I remember those days well and I hated it too! Don't worry though, time passes really quickly and before you know it you'll be the one talking about all those "annoying teens"!
(J/K, There are a ton of great adolescents out there, but the older I get, the younger everybody else seems! I'm 22, but sometimes I feel so much older!)
It's called generalization. Everyone has to deal with it at some point in their lives. I know it stinks, cause I deal with it all the time, but there isn't much else you can do except prove them wrong.
We all have been through it and I'm still not out of it yet lol. I just look at them and roll my eyes and ignore them and they will see in time that they were wrong.
Unfortunately only the bad ones get in the news, it seems. Makes the whole lot look bad. You just keep being a hard worker and respectful of all of your elders (like us old people), make good grades, and do some volunteer work. Then you can show you're not one of them. Pull out the usual teen "life is crap" attitude, and you'll be thought of as one of them.
Been there, done that. (I think. It's been so long, I can't remember.)
Ditto and after you go into college, things toned down and when you get to be our age, you would think likewise. NOT all teens are bad, I have two nephews, one is BAD to the bone and his brother is an Angel and very good student. Maturity will catch up with them and they will settle down, reach their goals in finishing college, start having a family and steady income.