Most people untrainned in science assume that "theory" and "opinion" are equal. They are not. A scientific theory MUST explain a class of events and make predictions about what those events will do latter on. A theory is closer to fact than hypothesis is to theory, and intelligent design doesn't even come close to being a scientific hypothesis let alone a theory...
ID/Creationism needs to be taught in a politics class because more than religious or scientific the ID/Creationism is about religious fanatics gaining political clout. As a pseudoscience, no science class should even acknowledge it more than it should astrology, paranormal instances or magik. It'sa political issue more than anything.