Dear ,
You will have to score 33%in each of the examination to pass. You can't just say that you will get 33% in finals and you will pass the class. But I will suggest you not to focus on the 33% . you surely have the potential to  score a lot more than that.

1 Try being thorough with the ncert textbooks. As much I know questions in KVS examination always comes from within the books. You will not get anything out of course.
2 Make a timetable.
3 Try learning more.
4 Practice writing your answers rather than just learning them by heart. This will help you retain the answers for a longer time.

Try doing these and you will surely score good marks.