Why the people that you would find in many high schools in the USA would be fake, immature, etc?
We do not educate them to be a good person. We teach them to learn facts and teach to standardized tests. We do not teach them to be free thinkers. We are assembly line education.
You'll find bullying and other bad behavior in European schools. I used to live there and knew people with kids. Many of the same things that happen here happen over there. You'll also find "superficial, tacky, and stupid" people there. Don't kid yourself for a moment that all Europeans are somehow brilliant and deep. They're mostly just ordinary human beings like everyone else everywhere. Did you actually attend the schools at length? Talk to parents about what their kids were experiencing? Frankly, if you were a foreigner talking to American high school students for a little while, you'd find a lot of THEM mature and friendly-seeming, too, but you wouldn't be seeing their interactions with their own classmates on a day-to-day basis. One significant difference does involve career preparation and university admissions. European students are often either enrolled in vocational training while in high school or are preparing for a whole set of difficult exams that will determine their admission to university and thus their lives. University education is structured differently there -- you go straight from secondary school into medical or law school, for example. So, some students may seem more serious (they are also extremely stressed) because of that difference.
One major difference is that we don't put all teenagers into the same "highschool". After elementary-school, those that like school the most go to one type of secondary school ("grammar school") after which they can go to university. the other "above average" go to a second type, and the rest goes to a third type
partially because of t.v.s shows, cartoons like Beavis Butt head, Simpsons, South Park, "F.R.I.E.N.D.S", etc but ALSO due to just genetics, it is not really a secret that the MAJORITY of the immigrants to the USA were not the "top people" or even "middle people" in the societies they came from.
The old "Europe is better than the USA" thing..I wouldn't suppose you're a liberal?
The USA as a whole is anti-intellectual and just not very smart. They’re more into sports,music,sex,and materialism than critical thinking and real events. Unfortunately, we just have to get used to it. It’s not going to change.