I don't understand the problem at all. Even if you believe fully in evolution and believe creationism is totally false, WHY do you want your children to be closed-minded and ignorant to different theories? Doesn't everyone want their children to learn everything they can? Why shouldn't they learn about both?
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There is nothing wrong with them learning about both. What is wrong is when ID is presented as science, when it manifestly is no such thing. I would be just as annoyed if kids were learning that astrology is science. Now, that is not to say that tID and astrology cant be discussed in school, perhaps in a lesson on the philosophy of science as demonstrations of how science differs from pseudoscience. Or maybe in a class on mythologies and beliefs.
Or, a study of evolution as pseudoscience, by your lights.