I'd say that no matter what school you are in, it's always the same. I'm 28 so it's been a while since this time in my life, but I'd say that, like others have said, the biggest thing is to just be yourself. Be yourself, follow your interests, and don't change for anyone. Unless of course, your interests change naturally. But don't give in to peer pressure. Don't give in to people pressuring you to swear, smoke, change your tastes in music or clothing or interests if you don't really want to. Or whatever it is they are trying to make you change. Don't listen. One of my biggest regrets is that when I was growing up, I kept my interests to myself. I did this so that I could make myself as small a target as possible. But in doing so, I was giving other people power over me. I think this stunted my confidence. And the thing is, the people who really wanted to put me down did anyway, so making myself small didn't even help anything. I liked things like Star Wars and Transformers and I played with action figures and LEGOs and stuff like that well past the age when most people stopped. I also didn't swear, smoke, or do anything about girls. I didn't want to. I also didn't express myself outwardly - even in high school, I didn't wear clothing that expressed who I really was, I tried to be plain and unnoticeable because I didn't want to deal with getting mocked for beign a "nerd" or a "goody two shoes" every day. If I could do it all over again, I would have worn my interests on my sleeve and who cares about the consequences. I'd have worn my Star Wars shirts with pride
The people who are good and nice and friendly will always be that way, and unfortunately, there will also always be jerks who enjoy putting others down because they have nothing better to do. It's not your fault, it's theirs. Don't let them stop you from enjoying yourself as much as you can because you are only young once and you will never be this young again so don't waste it.
Also, don't worry about joining the "in" crowd. I'd say completely disregard them. Don't go out of your way to be mean to them or anybody else, of course. But don't let them walk all over you. Don't let them push you around. Don't treat them any differently than you'd treat anyone else. Don't be untrue to yourself by changing your interests, don't suck up to them. They aren't special and they don't own you.
And if you don't feel up to doing anything about girls, I'd say don't. I'm a little more down about my chances because I am much older and things are different now, but if you are only a freshman in high school, then you have plenty of time to meet someone. Who knows - the person who is best for you might not even be someone who goes to your school. If you are as young as you are, you have time to not worry about it. That's another thing I'd enjoy if I were you. I don't like worrying about it now, but I have to because my chances are growing smaller and smaller by the day. But you don't have to worry about it yet.
Finally, be a kid as long as you possibly can. I wish every day that I could go back.
