To that end, I ask all high school teachers to stop teaching students the distinction between "fact" and "opinion" and replace it with the more conceptually coherent "belief" and "knowledge." The fact/opinion distinction that you seem to teach is a mutation of the fact/value distinction combined with total relativism about values, blind dogmatism about facts, and the bizarre notion that if an empirical issue becomes controversial enough, it becomes a value issue.
Here is an example of the pernicious effects of high school education. I asked a student why the following sentence was badly written, and if he could rewrite it more clearly.
My reasoning for disregarding Rachels arguments is because I feel that there is a moral difference between active and passive euthanasia.The student replied that what was wrong with the sentence--grammatically!--was that it was a matter of opinion. Someone had told him in high school that you cannot write down beliefs on ethical subjects because they are "opinion." "Facts" on the other hand, you can write down, because you really aren't involved in them at all. When you write down a fact, you are not asserting a belief about the world, it seems. You aren't supposed to be involved with it at all. Indeed, there seems to be no distinction between the fact in the world and the representation of the fact on the page.
Just stop it. Stop teaching students philosophically incoherent nonsense. The distinction between belief and knowledge is much clearer and more useful. You can have beliefs either about ethical issues or empirical issues. Those beliefs can be right or wrong, and justified or unjustified. When you assert a belief about the empirical world, you are still involved with it. You need to justify and support it. When you assert a moral belief, there is still the possibility of being right or wrong. If you belief is true and justified and perhaps meets some other criteria, it is knowledge. We like knowledge.
You know who else propagates this stupid fact/opinion distinction? Journalists. Y'all need to knock it off, too. The distinction between the "reporting" and "opinion" sections of the paper is completely incoherent. For starters, by journalism's own standards, the opinion pages are full of reporting and the reporting pages are full of editorializing. But worse, on both pages we get assertions of belief without justification. It is all authority with you guys, and not very good authority either.
Stop it. Just stop it.