Old theories such as phlogiston are now believed by nobody, and so can be comfortably taught, not as an alternative theory, but as a predecessor of modern theory.
Intelligent Design doesn't really fit this bill.
For a start, it isn't really a predecessor of evolutionary theory except in the loosest possible sense. The real predecessor is creationism, which was dogmatic, and not necessarily accompanied by any argument whatsoever. Some philosophers (e.g. Aquinas) did attempt it, but not just by argument from design; they also attempted the ontological argument and other such mumbo-jumbo. So we can't really legitimately teach Intelligent Design per se as history.
Secondly, some people still believe it. This might be seen as a good reason to teach it as current theory, except that AFAIK it is an unbelievably small minority of professional biologists who believe it, plus an unknown number of non-scientists. So teaching it would be rather like teaching the theory that life came from Mars - some people do believe it, but it isn't really a credible or interesting theory, and certainly isn't central to the corpus of modern biology.
Thirdly, it is a theory that cannot be disproved. Think about it; what evidence could possibly convince us that Intelligent Design was untrue? Even if evolutionary theory were to be categorically proven (not possible), the very fact of evolution could be a testament to the Designer's ingenuity. So it isn't really scientific at all, unlike phlogiston (and flat earth theory for that matter) which at least can succumb to evidence.
So I don't really see the rationale for teaching ID in science classes - perhaps it could be argued as a component of philosophy or religious studies classes (to go alongside Aquinas' arguments).
no subject
Intelligent Design doesn't really fit this bill.
For a start, it isn't really a predecessor of evolutionary theory except in the loosest possible sense. The real predecessor is creationism, which was dogmatic, and not necessarily accompanied by any argument whatsoever. Some philosophers (e.g. Aquinas) did attempt it, but not just by argument from design; they also attempted the ontological argument and other such mumbo-jumbo. So we can't really legitimately teach Intelligent Design per se as history.
Secondly, some people still believe it. This might be seen as a good reason to teach it as current theory, except that AFAIK it is an unbelievably small minority of professional biologists who believe it, plus an unknown number of non-scientists. So teaching it would be rather like teaching the theory that life came from Mars - some people do believe it, but it isn't really a credible or interesting theory, and certainly isn't central to the corpus of modern biology.
Thirdly, it is a theory that cannot be disproved. Think about it; what evidence could possibly convince us that Intelligent Design was untrue? Even if evolutionary theory were to be categorically proven (not possible), the very fact of evolution could be a testament to the Designer's ingenuity. So it isn't really scientific at all, unlike phlogiston (and flat earth theory for that matter) which at least can succumb to evidence.
So I don't really see the rationale for teaching ID in science classes - perhaps it could be argued as a component of philosophy or religious studies classes (to go alongside Aquinas' arguments).