Central Board Of Secondary Education [CBSE] — Not satisfied from the marks of Science and Maths.

I am Somil Vats from Saharsa, Bihar. I read in Shanti Mission Academy. My Roll number is 22257263. I got very less marks in Science and Maths and got very less percentage as result. And I am really unsatisfied from this percentage. I got 18 marks in theory exam of Maths and 31 marks in theory exam of Science. Even I got only 54.6% as result. I could achieve much better than this marks and percentage. On asking about this problem, school management excuses that the assessment team didn't follow the marking criteria 10-30-40. I regularly get above 70% in all internal exams and more than 70 marks in Maths and more than 80 marks in Science. Please take some serious action regarding this matter.