Here, from The Guardian, is the best explanation I've read yet of why "Intelligent Design" (ID) cannot reasonably be taught in any classroom as part of a biology or science (as opposed to history or comparitive religion) curriculum. It goes beyond this:
When two opposite points of view are expressed with equal intensity, the truth does not necessarily lie exactly half way between. It is possible for one side simply to be wrong.
and beyond even this:
[ID] no more belongs in a biology class than alchemy belongs in a chemistry class, phlogiston in a physics class or the stork theory in a sex education class. In those cases, the demand for equal time for "both theories" would be ludicrous. Similarly, in a class on 20th-century European history, who would demand equal time for the theory that the Holocaust never happened?
If complex organisms demand an explanation, so does a complex designer. And it's no solution to raise the theologian's plea that God (or the Intelligent Designer) is simply immune to the normal demands of scientific explanation. [...] You cannot have it both ways. Either ID belongs in the science classroom, in which case it must submit to the discipline required of a scientific hypothesis. Or it does not, in which case get it out of the science classroom.
The article restates (much more eloquently) something I wrote here just a week and a half ago: "Evolution is a fact: as much a fact as plate tectonics or the heliocentric solar system." And it is so whether we choose to believe it or not. Not only that, but it was so before there was anyone around to believe anything.
We humans developed science, and continue to use it, because it is a remarkably reliable way of finding out what's really going on—even when it uncovers uncomfortable things. In step after step, from the discovery that Earth is a planet and the sun is a star, that they are both profoundly old, and that the universe is far vaster than most of us can begin to comprehend, we have found out more and more that we are not the centre of the universe, or even at all important on the scale of the universe. And we may not like that. But the truth doesn't care whether we like it. It just is.
I would prefer that we made it our job to learn what is, rather than simply to go along with what we wish would be.