So many things it would be quite a task to list them all...
America is quite a crazy phase right now lol, sometimes I feel like a stranger in my own country.
It's funny because I see so many Americans look at other parts of the world and talk about how primitive they are - the middle east as an example, but we have people here who are trying to get evolution removed from schools, are densely xeno/homo/everything phobic, deny scientific fact, think the earth is 6000 years old, think Obama is a secret Muslim.. base their political and social views solely on emotional responses etc. It's almost like a big chunk of the populace is adverse to factual information.
Every country has people like this, but here they are part of an ascendant political movement, are firmly rooted in the culture and this kind of thinking is pretty much mainstream in some parts of the country.
Even outside of my own political biases, American culture is all about being stupid, loud, and ignoring the other guy.. and i've never liked that. There are good sides to being opinionated and vocal about ideals...but only when you actually know what you're talking about - which most American's don't, about most subjects they seem to like talking about.
Also I agree on teenage culture, but teenage culture is always retarded..it was (a long time ago) when I was a teenager too...however I will say that today's teenagers listen to much worse music, we at least has some sense of taste
Really hate dubstep.