Every debate that I have been to between evolutionists and creationists, the evolutionists always make the creationists look like a bunch of "C" average middle school kids. The only thing that scientists can't tear apart is the faith that creationists have.
The problem with allowing the teaching of creationism in school is it allows room for other mythologies to seek their way into the classroom. Think about it. Would you want your kids to learn that the world came from a giant egg laid by a gigantic chicken in some creation myths?