My biology teacher in school took a simple approach to a very religious classmate of mine when we were covering evolution. He just said 'Pointythings' friend, you don't have to believe what you are being taught. You just have to demonstrate that you have taken it in and understood it when the exam comes along'.
I think if we start including too many asides - as in including the full range of creation myths alongside evolution - there wouldn't be enough time for the important stuff.
As I have said upthread, it would be nice if we could have more teaching on the history and philosophy of science, and where those things intersect with RE, it would be interesting to have teachers from all three disciplines involved. It could be done in the form of a forum, with debate encouraged and the emphasis on demonstrating critical argument and sound reasoning. That would be fun.
However, I maintain along with most of the posters on here that creationism and ID do not in any way hold equal weight with evolution as scientific theories, and so they should only be taught as an aside - any more substantive teaching should be restricted to RE classes.