Okay, I usually avoid debate, but in my eyes education is one of society's most valuable assets, so here we go...
What in the world is the Texas School Board trying to do other than breed good little Republicans? Now, I don't expect said board to include large amounts of liberal propaganda in their textbooks, and it's true that in such a conservative state there's going to be an inherently right-wing slant to the educational requirements, but there comes a point where a bias becomes outright propaganda. Furthermore, some of this absurdity doesn't even gel with (reasonable) conservative views I've encountered. For example, most of my conservative friends very much value justice, and certainly seem to believe in responsibility to the public good - just not in quite the same way that a social democrat such as myself does.
I believe that all education, from Kindergarten classes to doctoral studies, should be based on facts - the most accurate facts available at the time, even if sometimes we come to the inevitable conclusion that "oops, that wasn't quite right." The presentation of those facts should be age-appropriate - I'm not proposing lectures on gender studies in Kindergarten. On the other hand, whitewash, spin, and propaganda should be wiped out where spotted. Consciously calling for them is just another nail in the fence between primary/secondary education and genuine academia. If we're going to water down the social sciences this much (and don't get me started on what we do to the natural sciences in school, especially biology)then we're doing our children a tremendous disservice. Teach students real history and they'll understand their world - teach them history with this much political agenda and they'll understand the world the right wing (or left wing, I can see this happening in the opposite direction) wants them to see.