Scientifically, both belong in the classroom. BUT it should be made clear that the above is the truth. In addition, neither concept has been introduced as a law, according to the scientific method. That should also be made clear.
ID does not even rise to the level of a hypothesis. A hypothesis requires specific testable criteria. ID does not have that. IS is, at best, a philosophical idea and has nothing to do with science.
In science, Laws are essentially another word for theories. For example, Newton's Laws of Motion are the basis for the physics taught in high school. These Laws are flawed and have been disproven by relativity. There is solid, observed evidence that shows Newton's Laws don't work but there is no observed evidence that Evolution doesn't occur. Why are Newton's disproven theories being taught without issue, but Evolution is such a sensitive matter?
First of all, a law and a theory, when it comes to scientific writing, are completely and traditionally different. A theory is a coherent explanation for a large number of facts and observations about a particular scenario.
A law differs from a theory in that it's a principle that consistently holds true under certain circumstances. Right now, evolution hasn't been demonstrated in real time outside of a laboratory, and it isn't completely in its results. That's what makes it not a law.
I definitely agree that evolution fits the category of theory much more than hypothesis. However, ID can be considered a hypothesis. Yes, I admit it's loose and does border on the metaphysical, but it still falls into the category of a concept that can be experimented with, as we have definitely done as humans.