I feel that my English teacher is unfairly grading my essays; what should I do?

From your earlier thread regarding physics:

http://talk.collegeconfidential.com/high-school-life/2102877-i-just-got-a-50-on-my-ap-physics-test-should-i-drop-the-class.html
and look at what your English teacher has said:

So this is probably the reality - you are not on the same level as your classmates

Now reread what else you wrote here:

I think you nned to relook objectively - the issue is not the teacher. Nor is it you, per se, but the fact that your old school was not at the same level.

As for next steps, I agree with @momofsenior1 . Good luck.