Im going to a new school this year. Its the same town, just  a different school from every single one of my friends. I only have two of my guy friends there, and theyre always hanging out with their group of guy friends. They feel unaprochable to me during a time such as lunch. The first few days, I sat by myself at lunch, and was quiet during PE. But now, day #4 of school, and I have a few friends. I met a girl from my Core (which is your three basic subjects, in which you stay with generally the same people those three periods), and went out to lunch with her on day #3. I ate with her, and one of her friends. Then, today, we sat with her other two friends, and before I knew it, I was surrounded by 4 other girls, talking and laughing at lunch. Ive also been talking with people in my Home Ec and Math classes. 
But see, by day #2, when I was still quiet all day (except for when answering a question, taking roll, and chorus, of course!) I wanted to transfer back to the other school where all my best friends and just plain friends were. But now I have a great time at lunch, Im not alone, Im finding myself able to talk to other kids in my other classes, and I personally think that I improved greatly.
Bottom line of this story, for anyone who doesnt know anyone at your school, or in your town for that matter, dont give up. Dont just automatically think, "This isnt working out! I want to go back home!" or, "I want to transfer to my friends school!" or something of that sort! My mom said, "Just finish this year, and if you still want to switch, then you can!" Dont give up on day #2, or day #3, or day #4, or day #10. You need to give it some time, and everything will be alright.