Since I am feeling chatty I will attempt my own summary of the reasons
for creationism in schools. I'm not a creationist, btw, but I even have my own reasons for wanting time spent on it in schools.
Here are what I see as the normal creationist arguments:
1) The Equal Time argument
The idea is that there are only two competing views of approximately equal merit. If that is the case why not teach both of them in the classroom and let the kids decide for themselves.
2) The Morality Issue
Evolution leads to immorality so it is dangerous to teach in schools. Only the Bible should be taught.
3) The Idea that creationism (or perhaps ID) is Right
This is based on the idea that evolution is wrong (or starting to appear that way). We should teach the "new" idea in schools.
Now I have my own reasons for suggesting that creationism actually be taught in some detail in schools.
1) A detailed examination of the arguments and so-called evidence for the ideas of them all, from YEC'ers to ID'ers will show up just how foolish they actually are as science.
2) A discussion of the theological issues (by real theologians) would show up just how dangerous to Christianity that creationism is.
3) The discussions and comparisons of the arguements of both sides is an interesting (if somewhat complex) case study in how to reason and how to understand the use of evidence.