Whether we like it or not, as teachers we influence what our students think. We shape what they find interesting and important, and potentially what they come to believe. To think otherwise is naive: expecting teachers to leave their perspective at the classroom door is asking them to do something that is not just difficult, but impossible.
This makes some people feel uncomfortable. What right do teachers have to bend pliable minds to their way of thinking, they ask? But this supposes that students cannot think for themselves and develop their own opinions. It implies that personal opinion is always a negative force. Neither is true. And although we cannot rid ourselves of perspective, teachers and schools can try to control when and how it is manifested.
But how do we do this? The case history on the subject is confusing, to say the least. There is no template for sharing ideas in a way that benefits learning - just an ongoing series of inconsistencies about what is acceptable.
For example, a history teacher in England was removed from her post last year after being accused of making racist remarks to a nightclub employee. She was not at school when the incident took place but it was judged inappropriate for her to return to teaching.
With this incident, the message is clear: if a teacher has a harmful perspective, we do not want it in the classroom. Schools should guard against any possibility that a teacher's views could hurt or negatively influence students in their care.
Yet in 2010, another teacher in England was allowed to keep his qualified status despite the fact that he used his school laptop to post anti-immigration comments in an online forum. He was an activist for the far Right British National Party but he claimed never to have shared his views with students.
Here, the message seems to be that it doesn't matter if a teacher has controversial views as long as they are kept away from young people. Understandably, many commentators point out that a teacher's views might change how they act towards certain people or the way they present ideas in lessons.
But it is not just offensive behaviour and prejudice that schools need to be wary of. Teachers might hold perspectives that threaten the integrity of their subjects: someone with strongly held views could easily (and accidentally) skew the presentation of material, resulting in students not being offered the whole picture.
For example, a teacher in Iowa, US, was dismissed last year for persistently claiming that the novel The Adventures of Huckleberry Finn was racist and should therefore not be taught in schools. At her appeal, the judge pointed out that the book was about racism and the whole idea of studying it was to highlight the issue. In the judge's view, the teacher had no basis for airing her views to the detriment of the lesson content. She was altering students' opinions by degrading the book, it was decided.
The whole issue of perspective is further complicated because few of us have a problem with schools imparting ideals to children per se. Schools are held together by values; that is what we mean when we say they have an ethos. We don't feel the need to explain why friendship is good or why tolerance is better than intolerance. We do not seriously question whether women should have the vote. Like the Founding Fathers of the US, we hold certain values to be "self-evident". We do not have a problem with fairness, equality and tolerance being taught in schools because we all agree with those ideals.
The debate rages on
But we have to be careful about believing that this "we" is universal. What constitutes a controversial view changes over time and in context. Nearly 90 years ago, the US state of Tennessee prosecuted John Scopes for teaching the theory of evolution. Many would have expected modern science to quash that debate, and yet the place of creationism and evolution in the classroom remains an extremely contentious topic. Just look at the heated debate that took place in the letters pages of TES in response to the story "Creationism: a `very real threat' in schools" (17 January). Perhaps we are not as far removed from Scopes' experience as we may have thought.
And perspective is an issue not only when a viewpoint is deemed controversial. For example, religious education teachers have to think carefully about their answer to the inevitable question: "Miss, do you believe in God?" If they answer truthfully - either yes or no - many wonder if students will feel that they are being encouraged to believe, or not to believe, because of their teacher's views.
Alternatively, students who do not share this belief may be put off the subject. If the teacher is a Christian, children with different faiths or none may no longer feel that the classroom is a forum for their views.
This is not a problem unique to RE teachers. A science teacher's atheism might change the slant they put on evolution. A history teacher's feminism might affect lessons about Elizabeth I. A geography teacher who has worked for a charity such as Voluntary Service Overseas may have a distinct take on global development.
First do no harm
Perspective affects us all. So what should we do about this seemingly insoluble quandary? How do we steer students to their own viewpoints without leading them to our own?
There is a simple rule that we could employ here. Inspired by the English philosopher John Stuart Mill's harm principle, (which proposes freedom up to the point that someone might be harmed), we could say that a teacher's perspective has a place in education up to the point that it undermines effective delivery of the curriculum. When a perspective compromises a lesson - either by swaying, offending or alienating a student - then it has impaired learning, so something is wrong.
You can check for this against students' reactions, the ethos of the school (which parents will have bought into when they decided to enrol their children) and your own judgement as a teacher. Don't be afraid to ask trusted colleagues for their views and discuss your thoughts. Being aware of any bias you may have and being prepared to tackle it will thwart many potential problems.
These discussions and checks are not just necessary for the views we express in the classroom but also the ones we publish online or make public in other ways. Students always see us as teachers, regardless of the context. Although we should have some freedom in private, we must always be vigilant.
We should also be unafraid to tackle the issue of perspective with our students. They are capable of understanding the idea that everything they hear is not pure truth. A good example of this capability came up in one of my sixth-form classes. We were discussing perspective and, as we sat facing one another around the table, one student had a realisation that no one was seeing the same aspect of the room. And more than that, no one in the room had the objective view. So talk to your students and be willing to let them challenge your views.
However, we also should not forget that teacher perspective is often the thing that makes a lesson work. All schools want teachers who are passionate about their subjects. If you think back to your most inspirational teacher, I doubt that he or she was a neutral voice presenting all material in the same way. Brilliant teachers give something of themselves in lessons - a take on the subject that comes from their experience. Engaging teaching requires perspective. But we have to be more considered in how we use it.
Clare Jarmy is head of philosophy and religious studies at Bedales School in Hampshire, England. She is the author of Arguments for God, published by PushMe Press, and forthcoming education study guides on the miracles and attributes of God
Do you agree with an educational consultant who believes the politics should be taken out of teaching?
Or are you on the side of a teacher who thinks his colleagues should nail their political colours to the mast?