.... this looks fine to me; you introduce the topic and express your opinon... that's what they expect with the introduction :)
To start with,let's refer to the main responsibilities of a teacher;aA teacher should impart knowledge, encourage his students to think outlogically andthings independently , inspire his students' mind and of course get his students pass the exams .
... I introduced some changes... Good sentence :)
In addition, making his social and political views known to his students doesn't improve the quality of teaching.
In addition, in my view, his social or political views would not have any bearing on improving the quality of teaching.At this point you should give a more specific example.
Inversely, it will lower students' learning efficiency. Because students holding different opinions will start to argue with each other and even quarrel in the class, which will definitely make harder for them to focus on what they are learning.
.... this line looks more or less like another reason and not a specific example. You can turn that into a specific example;
For example, suppose a teacher expresses his political views in the classroom. There can be a student who holds different political views and may try to defend his views by arguing with the teacher. This might ends up in very unpleasant situation straining the relationship with the teacher and the student. ...now it looks more speicific :)
You write well and wish you good luck!