Science
1
Clarification #1: I am rating this 1 star because science is not a religion, or at least it should not be a religion. Unfortunately, in my study of high energy physics, I have ran into more than a few physicists who do treat it as if it was.
Clarification #2: As you read this review, you should probably know that I am a practicing Catholic.
Scientific theories such as the big bang and evolution are valid theories that should absolutely be taught in science classes. For succinctness, I will use "creationism" when describing the view that the big bang and evolution are incorrect. (I personally don't like this definition, because I believe that God created everything, but I most certainly find scientific theories such as the big bang and evolution to be valid. So technically, I guess I'm a creationist, although most wouldn't consider me to be one.)
"Creationism" is not science, and has no place in science class. It's that simple.
Now is where I have to outright disagree with magellan. Like it or not science and religion are not completely unrelated, because in the end, both deal in large part with the explanation of our existance. They shouldn't have to compete with each other, because science and religion deal with different aspects of our existance, and they use completely different methods. An oversimplistic view (and since it is an overly simplistic view, you will be able to come up with counter examples, I'm just trying to make a general point.) is that science deals with "how" and religion deals with "why."
Science has no good reason to say that God didn't start the big bang (Current scientific theories are rather lacking in "before the big bang" details). On the other hand, I can't find anything (in my interpretation of Christianity, anyway) in my religious beliefs that says that things like evolution and the big bang are wrong.
Science and religion are different things, yet in the end they are two pieces to the same puzzle.