I have some school problems..?

[Lubzz]

Hello I joined a school named The British School (T.B.S) a year ago, when I was in the 5th grade, 11-12 years old. I had fun but I had been bullied a little in that year. Ok let's talk about my 6th Grade experience.. it started 2-3 months ago:
My school started. I was nervous. I looked for my class room and finally found it.. When I entered the room, I saw a new BEAUTIFUL teacher seating in the teacher's chair. I went to sit when I saw my ex making faces because I was here.. I actually got a little angry but I tried to ignore him. Later my teacher told me to introduce myself.. I got nervous! I stood up, but I couldn't say anything, then the teacher said 'Don't be shy', I told her my name and sat down. A little time later my 'friend' came (She was a girl), she and I was the only girl there.. I saw a new boy joining our class.. she was shorter than me.. Ok Let's stop discussing about my 1st day in 6th Grade! ^_^
Well, my problem is that, The 'friend' I was talking about, I hate her. She has RUINED my life! from the beginning of the school, I bought a new notebook at the starting of class 6 & Started writing each and every important things I'd need. She saw this and started copying me. She kept reading ALL my notes and when I went to see hers, she did something so I can't see her notes! :O One day I searched for my notebook and I couldn't find it ANYWHERE! I told Her if she has seen it, she said no. The next day she told me she'll search her house if she has the notebook. the next day she told me she has the notebook and gave it to me. Isn't it a sin to steal! :'( and one day I went to look at one of her answers and she grabbed it from me as fast a possible so I CAN'T see the answer! I read the first lines and it matched EXACTLY like mine! How COULD she do that! I was SHOCKED! These are just SOME of the things she has done to me! I hate her so much! Besides that, one day (IN 6th grade) she told me about her problems she have with me. then she told me 'u r not my FRIEND anymore.' I have tons of problems with her but I don't tell it to her. I think that I am prettier than her, and a senior friend of mine has told me that I am prettier than her. But 2 boys in the class thinks SHE's prettier than ME! Why so?! What do I need to improve! She's way fatter than me although she's smaller than me! But my senior friend told me that a lot of people he knows hate her.. what can I do to solve this? and I am going through really well with the teacher I talked about, and when I asked her who's her fave student (In Facebook), she told me to keep it a secret, It's me! I am liked by some people but why do She and 2 of the people in my class hate me? Does anyone have any really good idea to stop her and be better than her? Thanks for reading