>>1 What Anri said, be yourself. If these people don't matter to you then you've got no need to impress them. However, don't take that as an excuse to be an asshole towards them - you need to build these social skills and tolerance towards such people to advance in life.
Stupid teenager shit is a part of life. It's a lesson to learn - you learn to be better than the things you hate. It teaches you not to judge based on things like looks and interests and to rise above all that bullshit to become a better person.
People now aren't growing out of that teenager bullshit as well nowadays, still acting like dumb teens well into their twenties. But the people who can't mature by that age are stupid, because you can't enter society and find a good job being that immature.
Equally so, you need to avoid judging them. There's no point calling them out on their idiocy when you're doing the same thing, because it's all about perspective. Don't care about their taste in music or their love of memes or their weird hierarchy, and most definitely don't be rude to them because of it. They aren't necessarily bad or stupid people, just not as mature as you. You just need to accept them - if they're going to be dicks, be a dick right on back, but don't get all funny with them over their choices just yet. After all, they're just kids.