Despite the shrill whines of the Creationists, rejecting their nonsense has nothing to do with disproving God, or trying to get ourselves out of some sort of moral obligation.
What it is about is intellectual honesty. As such, it's horribly dishonest to pretend that Creationism is a legitimate scientific theory and that it belongs in classrooms.
But given that science cannot comment on whether or not a supernatural realm exists, and if it does, what could be in it, we must be careful not to overextend the role of science.
Realizing this, teachers in the UK have been instructed that Creationism can be discussed in classrooms, but it must be made clear that it has "no underpinning scientific principles".
That sums it up quite nicely to me.