First of all I think you should stop worrying about your mistake in school because I doubt that you re the first person who done similar. You should explain your teacher that you feel sorry about what you did and that will not happen anymore anything similar. Explain her that you had a rough time at home but don t go in details, just say family issues and that you ll try your best with the assignment.
About your parent I think you should try to talk with them separately and explain them that their arguments and constant fighting influence on you.
If they have their problems they should go for a dinner somewhere out or for a walk and try to resolve it.
Just keep your head up and be positive bcoz after rain comes the sun.
This thread has expired, but why not create your own?