There would not be a philosophy (note I didn't use the term science) called ID if the education of our children wasn't at stake. Science is not insular, no matter what the ideals are. The belief that men are not in the image of God is profoundly offensive to Christianity. Making evolution compatible with it requires a rather thorough understanding of science and of what has been alleged and what has been proved. As as inculcation, 6th grade science textbooks often introduce evolution. I don't see evolutionary biologists coming from the 6th grade. The primary purpose of putting it there is to sew seeds of doubt. Much like Luther, evolutionists may believe it is good thing they are doing. Like the Reformation, there are plenty of people on the sidelines itching at the bit to manipulate whatever they can to pry people away from the faith. Advanced science such as evolution requires a different understanding than one has when they are 12. Science at that age (and for too many as adults) is often considered inalienable truth. As you probably know, later in the sciences you recognize that science is an explanation only as valuable as what it can imitate and manipulate. This is not to demean science, just to offer some perspective.Readers have probably caught on by now that I consider the theory of evolution to be the best current theory we have concerning biological origins of species on this planet (one tries to be careful and avoid phrases like "believe in evolution"), but it struck me this gets to some of the discomfort that many Christian parents have with allowing schools to present evolution to their children in science class.
Leave aside, for a moment, the question of what the history of life on earth actually is. Clearly, someone who believes that science can demonstrate that God created the world and all life on it via a miraculous event has less room to lose his faith in God than someone who believes that life on earth developed via a natural process -- but that God created the universe and the laws of order that allow it to be a welcoming place for life on earth. The more direct you think the evidence of God's hand in the universe is, the less room you have to doubt God's existence. (Now, if God had given us all "Child of God" birthmarks, we'd really be set...)
This leads some people, especially those who have little intellectual interest in science, to wonder: Why exactly should we be investigating these things anyway? We know God created the universe. We know that He intended each one of us since before the creation of the world. Sure he _could_ have used evolution. But since evolution is never going to impinge on our daily lives, and we only have to read the papers to see that many biologists use evolution to justify their atheism -- why should we teach our children about evolution? It seems like all danger and no upside.
Now, I don't deny there's a certain danger involved. And no one ever went to hell for not "believing" in evolution -- while quite a few people have gone to hell for refusing to believe in God. So I have no problem with people who have no interest in evolution. What does make me grumpy is when other Christians, because they like the idea of God's existence being readily demonstable in the scientific realm, seem willing to pile onto a biological theory they don't necessarily understand (and which may not be true) simply to thumb their nose at the specter of atheistic materialist scientists. But there is a danger inherent in ID. When we stake our faith on the back end of a bacterium, and say that we know there is a God because the flagellum is irreducibly complex, we build the house of our faith upon sand. There is a very good chance that the flagellum is not irreducibly complex, and if we have told countless people that God is to be found in the gaps, then when those gaps disappear so will God.
This is not to say that some scientists are not atheists, and that they draw on evolution as an explanation for why they "don't need God." However, evolution is no more capable of proving that we have no "need" for God than the theory that the earth rests on the back of a giant turtle, which is standing on another turtle, which is standing on another turtle and so on, could prove that there was no need for God to create the heavens and the earth. We know that the universe is a temporally finite. And we know that every effect in the material universe has a cause. And thus we must in the end either admit that some outside, eternal, uncaused force created the world -- else simply throw up up our hands and say, "The universe just is. I accept that it exists, but I'd rather believe that it exists 'just because' than that God created it."
The Hitchiker's Guide to the Galaxy tells us: "The universe is an incredibly big place. So big, in fact, that most people choose to live in a smaller one of their own construction." Materialists, no matter how highly degreed, live in just such a smaller place. We as Christians, however, do not have to. There's no need for us to hide from evolution, because even if turtles descended from more primitive turtle-ancestors, who descended from amphibians, who descended from fish, who descended in turn from something else -- we know that the turtles do not in fact go all the way down.