"Man evolved from monkeys" - that old tired straw man that creationists use to raise emotional hackles of people who haven't otherwise gotten evolved in the debate. Nowhere in evolutionary theory is it advanced that man evolved from monkeys. Both simians and hominids arose by descent with modification from a common ancestor.
Here's why we cannot teach creationism as an "alternative" in biology classes - apart from the fact that biology is a science and creationism is a spiritual belief, and therefore not appropriate in a science class, if we teach an "alternative" which one do we teach? The judeo-christian version? I don't know about you, but I went to a large public high school and the majority of the people in the top 5% of the graduating class were east asians - many of them hindus. It would be a violation of their civil rights to subject them to the christian belief and not discuss hindu creation story. Do we really have time to teach all of the religions of the world in two semesters, and give our students a decent introduction to biological science? No. This is the problem. Fundamentalists are biggoted. They don't want ALL beliefs taught in biology classes, just THEIR beliefs. You can believe what you want, keep yourself in the dark (Plato's allegory of the cave comes to mind) but don't push your biggoted ignorance on my children.
Really, it makes no difference that you fundamentalists vainly fight to push our education system back into the Dark Ages. The facts are inexorable. There is a story of Gallileo, who was called before the church, and under pain of death, told to recant his statement that the earth revolved around the sun. He did so, but then looked at the ground under his feet and muttered, "yet it still moves."
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