Here is a short video by A. C. Grayling on the question of whether there is a pedagogical obligation to teach both creationism and evolutionary theory in science classes:
I tend to think that Grayling is right. Teaching creationism next to evolution does seem to treat as worthy of serious consideration a view that simply isn’t–at least not in the domain of science. (That’s not to say that creationism and it’s implications might not be worthy of serious consideration in different domains–perhaps in religious studies courses.) I wonder, however, what this says about the teaching of opposing viewpoints in general. It is hard to deny the intuitive pull towards the idea that we are morally–and rationally–obligated to hear all sides of a controversy before making up our minds. Call this the “equal consideration norm.” When all the standpoints at issue are feasible it seems a sensible enough norm to follow. However, there are several controversies in contemporary public life where at least one side seems to trade on this otherwise intuitive principle to get it’s standpoint into debates where those standpoints might have a tougher time getting serious consideration on their own merits. The climate change controversy comes to mind as another example, apart from the one Grayling discusses in the video, that fits this pattern. I’m sure the reader can think of others.
What do we teach our students about navigating between the “equal consideration norm” and judging standpoints on their merits? Do we do our students a disservice when we neglect a particular “side” in controversies like these, in violation of the “equal consideration norm”? If not, when are we licensed to say that a particular standpoint in a controversy doesn’t merit serious consideration? Under what conditions do we allow the even stronger judgment that it would it be wrong to accord to a standpoint the honor of serious treatment of a controversial issue (the way that Grayling thinks it is wrong to include the creationist standpoint in scientific discussions of human origins or cosmology)?
Supposing we can work out satisfactory answers to the above questions, what ought we to teach our students about how to draw the line between views that merit serious discussion and those that do not without falling prey to prejudiced or biased modes of thinking?
RAIL 
We should teach the *process* by which to discern the views that “merit serious discussion” and those that do not. I like doing a “quick analysis” using the checklist suggested here: http://skeptoid.com/episodes/4037 . While not specifically meant to address non-science claims, as the author says, “When you hear any claim, run it through these fifteen questions and you’ll get a pretty clear idea of whether or not it has any merit.”
There’s some overlap between the questions on this list and candidate critical questions for arguments from authority–supposing one wants to work within the framework of arguments schemes and critical questions. In some circumstances I think that will work just fine, but I wonder if applying this method more generally might not be both too permissive and too impermissive. We see the former, I think, when we consider moral matters in particular. Many of the questions on the list won’t apply to such issues, it seems and as a result one might wind up having a discursive obligation to take seriously views that intuitively beg for dismissal–like the proposition that racism is socially valuable, or that pedophilial relationships are on a moral par with similar relationships between consenting adults. (Until recently I would have added to this list the proposition that a standing policy of interrogational torture is morally justifiable, but we’ve all seen what’s happened there.) Maybe we could develop a similar list for moral controversies, but I worry that this one might turn out to be too permissive.
The criteria on the list might also turn out to be too strict. While I’ll be the last person to dispute the usefulness of these questions for making benchmark assessment of claims, especially scientific claims, it seems to me that relying too heavily on such a list might lead to our excluding new or minority views that are respectable in many of these ways but just haven’t caught on yet. (Think of how “orthodox” natural philosophers would have applied questions similar to these to Galileo’s results, for example.) I wonder if following such a list doesn’t lead us into a problematic form of rational conservatism.
I have the hunch that one of the unexpressed premises of Mr. Grayling is that there is a direct relation between what it’s taught and what is known. We should not teach theories that do not deserve “serious discussions” has little to do with protecting those students from knowing what those “un-serious” “un-deserving” theories are about. But even if it where, I think the main peril is teaching them in the same manner as professors do with other “more serious” theoretical approaches to that same subject, not teaching them “at all”.