First, you have to question which creationism story is being taught? Because there is a different creation story for every established religion, and on that basis alone, one should question why exactly a judeo- christian creation myth and therefore God is any more likely than any other religion.
Second - No, creationism has absolutely no place in science classes except as by means of comparision ("this is what used to be believed" ) By all means, teach it in comparative religion, or myths and fables, alongside the Shinto, Greek, or Norse creation myths, but absolutely not in a science class.
@jno - Not sure if I understood you correctly. Are you saying we cannot teach evolution because we are still learning about the beginnings of the universe? I would disagree if so, largely because one has nothing at all to do with the other.
You also imply that because theories of a big bang origin are "random and inexplicable" to you, this is sufficient reason to afford a creator God an equal footing? I don't think so. Its a strawman hypothesis anyway, since we know a lot more than your comment would suggest. The genesis of the universe can be explained, with regular, mundane, non- superstitious universal forces, all the way back to about the first 1,000th or so of a second of creation.
Now, if your God wishes to hide in the remaining 1,000 th or so of a second of creation, a kind of "God of the incredibly small Gap", then fine, but that sort of a God, one that initiates universal creation, then takes no further part, seems very unlike any that are taught by established religions.
Keep religion in RE.