I'm really not sure what the issue here is, aside from people on the forum not liking the ideology of the Christian Right.
To me the issue is that - once again - a politician is using his office not to do what is best, or even what he necessarily feels is responsible, but using it to voice disdain of "experts" in order to cater to the prejudices of his base. "I don't agree with these experts, someone has to stand up to them" is Don McLeroy's stated motivation for the reforms he suggests.
I do not believe that the quality of an education is merely an abitrary measure. Were I to sign up for a course I would want to make sure I was receiving the knowledge I would need to best comprehend the subject - and I would want the same for my kids.
Don McLeroy might just want to subject biology, history and politics curriculum to a subtle revision at the moment. However, if he is just allowed to do that then what next?
When I want to learn something, the more "expert" a teacher is the better. If those experts are forced by elected politicians to adjust what they feel is best or most representative just because of that representative's disdain and appeals to popularity I think everyone suffers. If Texas children are being groomed to ignore the contributions of ethnic minorities to US history I think that sets a bad precedent.
Plus I'd also argue that denying evolution within Biology classes is akin to telling kids that "adios" is French for "hello".
And I think it's worth noting that the only state in the US to teach abstinence-only contraception is also the state with the highest teen pregnancy rate - Texas.
There is such a thing as a bad education. People shouldn't swallow it just because "well - he's our elected representative to the school board".
As far as I know no particular group has an agenda against math and the agendas contorting biology have very little to do with the functional biology taught before the university level.
Even if that were the case (and I think anyone who wants a basic education should get the uncontorted version myself) why should those Texan children who might like to study science at an advanced level should just have to put up with the fact they were taught it wrong during their formative years because of some vote-chasing politico?
Also, algebraic textbooks have been banned by the TBA on account of illustrative examples. So even maths isn't safe.