When it comes to whether teachers should let their political or social views known to students in the classroom, opinions vary, based on people's diverse backgrounds, experiences and values. From my perspective, I totally agree with the argument, considering that teaching should be as objective as possible.
First of all, teacher's views of the history of a country should not be known by the students. To elaborate, it's never a good idea to pass on the teacher's personal prejudice of the history to the next generation. History is supposed to be shown objectively, or a severe cognition error will occur. For example, one of my friends, Jason was a student of the Senior School of our town. When they were studying the history about the Civil War, their teacher regarded the war as a good thing and named it as "War for Peace". So in the next few years, Jason also considered the war as a honorable thing and always solved problems by violence. That caused countless problems such as bully in their class, which in turn exerted very bad influence on the teacher's teaching process. Therefore, an excellent teacher is not able to expose his/her opinions about history facts to his/her class.
What's more, teachers should not comment on some celebrities casually as well. That is to say, although some celebrities have either bad or good influence on the society, the teacher should not comment on their behaviors. Never should we ignore the significance of the teacher's opinions expressed during the teaching process. Students may take them as truth and hold strong belief in them. According to a survey conducted by the NYU, which invited up to 1,000,000 students in both senior and junior school students to complete a questionnaire, even 61.35% of them reported opinions that they believe in comes from their teachers and 54.3% found the opinions were wrong during their further insight into the celebrities. Consequently, comments on celebrities should be necessarily ruled out in accordance with what we have been talking.
Last but not least, expressing teachers' private arguments wrecks havoc on the students independent thinking ability. To be more specific, students may just sit back and receive the analysis from their teachers instead of trying to think the problems by themselves. It's very dangerous to cultivate laziness in child's mind.
In a nutshell, from we have discussed above, it's not beneficial but harmful for the teachers to make their social or political views known to students in the classroom. We should set up rules to regulate this behavior of the engineers of the soul of human beings.