I'm a teacher, so maybe I can shed some light on why many of us are so resistant to having ID taught in science classes.
Until intelligent design is thoroughly investigated in a structured and scientific manner like evolution, it isn't science, and simply, therefore, should not be taught in a science class. The scientific evidence supporting evolution so far overwhelms any scientific evidence of ID that it's ridiculous to consider them deserving of equal time in a SCIENCE class. My job as a teacher is to give my students the best available information and evidence. Anyone who has studied evolution in depth realizes that the evidence for it is overwhelming. Until ID can present a legitimate challenge to evolution based on scientific evidence, it doesn't need to be in the classroom.
And for those who say we might as well not teach anything about it and just tell people to research it for themselves and make up their own minds...that's ridiculous. That's like telling a student, "There are a lot of translations of this Latin poem on the Internet, so go find one and teach yourself some Latin." There is no substitution for learning in the classroom under the guidance of a more expert mentor.
Parents are, of course, advised to monitor what their children are learning in school, and if they want to, they can supplement those teachings with their own religious context--a religious context that does not need to be, and should not be, presented as science in public, non-religious schools.