Would anyone care to give their reasons as to why teaching BOTH creation and evolution in schools is wrong?
Well, there are several answers to your question.
The first, and in my mind most basic, reason not to teach creationism is that there really isn't anything to teach. If this sounds flippant, I don't mean it to be. The fact is that virtually every time a creationist is asked to put forward a positive case for creationism, the ensuing silence is deafening. Creationism is quite honestly little more than a series of
ad hoc, and largely misdirected, criticisms of evolution. There are very few, if any, actual claims made, hypotheses put forward, or theories propounded for a teacher to teach.
About the only significant exception to this is Intelligent Design. Compared to the rest of creationism, ID is a plethora of positive claims. Unfortunately, compared to natural selection, ID is quite anemic.
A second problem is that the methodologies used and the reasoning displayed by creationists are in direct contradiction to the methodologies and reasoning used by any branch of science. So, to teach both in one class would be akin to a math teacher saying, "We know that 1+1=2. But, at the same time, some people think that 1+1+1=1." In other words, it would completely undercut nearly everything else that the students are taught in the class.
A third problem, and probably the one that gets the most press, is that it's against the Constitution to do it. For all the effort that creos go to to try to show that there's a scientific basis for creationism, at bottom it really is nothing more than a religious tenet of a minor group of christian fundamentalists. Public schools have no business promulgating such beliefs.
Thus, it would be futile, it would be counterproductive, and it would be unconstitutional.
Those who would sacrifice an essential liberty for a temporary security will lose both, and deserve neither. -- Benjamin Franklin
We see monsters where science shows us windmills. -- Phat