My maths teacher hates me, she always shouts at me. She hit me once and she told me that i couldn't do anything about it, so what should i do?

How old, or young, are you? Let's be real for a moment. Your arithmetic teacher's job is not to let you or not let you follow you vocational dreams. It's to teach you and make sure you have learned so you can pass to the next grade. If you are not allowing yourself to be taught, or are doing things besides participating and learning the class curriculum, you are to blame and not the teacher. And it won't make a difference with another teacher if you insist on not trying to learn the lessons you are being taught. And you should consider one other thing . . . About musicians.

One of the hallmarks of all good and gifted musicians is that math aptitude and musical aptitude go together hand in hand: People who are gifted in music are also gifted in math; people with poor math aptitude generally don't succeed in music either. So you should consider carefully why you are in math class, and what it (not your daydreaming) will do to advance your music career aspirations. And remember, things only get more difficult as you grow older. If you can't concentrate and keep up now, what will happen later . . . When they don't "shout" to try to help you, but instead just throw you out. Think about it. Let us know if this helps at all.

You should talk to your parents if you haven't already and also talk to your school counselor.  There's no reason for a teacher to hit a child and yes you can do something about it, your last resort should be to go to the Principal.