It has been rejected by the overwhelming majority of experts in the field. While that doesn't by itself make it wrong, it's the only criterion by which school boards, administrators and teachers can judge what to teach and what not to teach.
Can you find individual experts who dissent? Perhaps. But the same is true of astrology, alchemy, homeopathy, geomancy...all manner of obsolete, medieval superstition, in fact...but we don't teach them on an equal footing with science.
Mention ID in schools, yes, but numbered among the list of rejected, old ideas.
And again, all I keep hearing is how ID has been discredited and rejected. How? Why? What is the bullet through the brain (or heart)?
Rejected, old ideas? Hmmm, something else comes to mind. Can't quite put my finger on it.