Since I'm a social scientist and not into the natural sciences I can't really say a lot about the proof of ID but I strongly believe that we should leave the preaching to the churches. There are many good arguments for teaching religion in school, but not only Christianity.
Considering the world we live in, we should teach our children about Judaism, Islam, Hinduism, Buddism and so on because of the impact religions have had on history and society. Many of the unspoken rules that are the basis of a functioning society come from religion and without them, society would probably not remain. On the other hand, considering ID to be the "Truth" and live accordingly would, to me, be like enforcing Old Testament laws on 21st century societies - anyone for a stoning, perhaps? I've got a neighbor that always works on Sundays
In my opinion, religion is a great tool in order to understand how modern societies came to be the way they are but to me that's where it stops. Nature vs Nurture? Nature might set the stage, but we are the writers, the actors and the audience...