Well, there's nothing you can do about your skin colour: we are who we are.
There ARE some other things you can do, though. The people making comments about you are ignorant and prejudiced, and maybe they need to be called out. Try letting them know you don't appreciate their comments, and also mention racism. Some people make comments without realizing how hurtful they are - if someone hears they are being racist, they might be shocked into shutting up.
Of course, it's not always easy to say these things to people. Do you have friends you hang out with who are vocal and more likely than you to stand up for something like this? Let your friends know how you feel - you'll gain their support and also probably find that they are insecure about their weight, skin colour, height, etc. Everybody has something they feel less-than-wonderful about.
Finally, I'd like to say that the things that make people most uncomfortable when they are teenagers are often the things that make us proudest and strongest as individuals. That's why many young black people, gay people, or other minority people end up joining groups in college - you finally are in a place to be proud of who you are.
I don't know how to help you get to that place. But I think you should stand in front of a mirror and think about all the things that you do like about yourself - if you take away any tiny piece of who you are, you become a different person. Your feelings about your skin colour are giving you an experience no one else can have, and that's really valueable.
If you see yourself as unique and proud (because you have nothing to feel ashamed about), then it might be easier to accept yourself. And if you come across as a person who is confident in herself, then other people will recognize and respect that.