The argument is still whether or not this is to be taught in class, or both? It seems intelligent design speaks of the creation of the species on Earth, and evolution talks of the development. The Big Bang is part of science, and so is evolution but they are not closely associated. They say the Big Bang has gaps. This means that the theory is not 100% true, and neither evolution, intelligent design, or the Big bang have been confirmed. The big bang is more closely related to intelligent design than evolution is to intelligent design. This saying that the big bang and intelligent design focus on how we were created. There is some estimates of the big bang. An example would be the galaxies moving apart, which they claim is from the big bang. But if they make assumptions of how it looks like the big bang was formed this way, then the estimate of the "propeller" on the flagellum and how it looks like it was designed could support intelligent design as much as the big bang evidence can. Then why is the big bang allowed in schools and intelligent design isn't? This is because the big bang has more evidence, http://en.wikipedia.org/wiki/Big_Bang. The big bang is something many people are not familiar about, and the concept of it being associated with evolution is incorrect. They are both science, but different areas of science. The argument between evolution and science is whether enough how many facts there were in the argument, the judge declined intelligent design because of little support behind the theory, and evolution seemed to have much more support. The judge decided for intelligent design to not be taught in school.
Intelligent design should not be taught in schools, because there is not enough support for it to be proven to be a solid theory. What is the difference between a theory and a theorem? A theory (dictionary.com): a proposed explanation whose status is still conjectural, in contrast to well-established propositions that are regarded as reporting matters of actual fact. A theorem: A proposition that can be deduced from the premises or assumptions of a system. The theory of evolution is not a theorem., they say there are gaps in their hypothesis, and the theory of intelligent design is not proven either. So neither evolution or intelligent design are 100% proven theorems, but evolution is taught because of more evidence found upon its theory.