Is it accepted that a teacher help his students by canceling for them some subjects not included in the exam to mitigate or relieve them?

the goal of the exam is to test the students and to know how much of information they become familiar with.

the teacher goal is not to help the student to get high marks, but it is only to teach and direct them and develop their ability.

Teachers and family have to support the children whatever the mark will be

Hi, I always tell my students which parts is more important for exams and what can brought their scores up, plus in extra times i try teach them those points due they don't miss any informations.