Gregg Easterbrook does a good job of defining the explanatory scope of evolutionary theory while talking about the Cobb County, Georgia disclaimer on biology textbooks.

Darwin's hypothesis and its contemporary interpretations (usually called the "synthetic theory" of evolution for reasons that don't matter here) concern how living things, once they exist, respond to changes in their environments. That living things evolve in response to changes in climate and competitive pressure from other living things seems as close to certain as any assumption of science.

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None of this bears on "the origin of living things," which ranks, with the origin of the firmament itself, with the deepest mysteries of existence. Darwin's theory of evolution is silent on how life began--the great man took pains to say that he did not have the slightest idea.

Good explanation.

The actual disclaimer says:

Evolution is a theory, not a fact, regarding the origin of living things. This material should be approached with an open mind, studied carefully, and critically considered.

Easterbrook complains that the disclaimer is stupid because it incorrectly describes the theory and what it purports to explain. But it isn't entirely off the mark. Evolutionary theory does explain how species arise, and in that respect it explains the origin of the variety of life forms. But he's right that it doesn't explain the origin of life itself.

Whatever. I think the disclaimer is dumb because:

1) It's selective (students should approach everything they learn with "an open mind" and it should be "studied carefully, and critically considered"...duh.

2) It is obviously selective for an ulterior reason, mainly religious objection to the implications of evolutionary theory.

So pick your reason...any way you look at it it's stupid.