I agree with Thanz on this one 100%.
Corplinx does bring up a good point though.
How much of a right wing/fundamentalist bias is there in the education system?
To me the rightwing/fundamentalist bias is increasing in both middle and high school bias has been increasing. (i.e. Creationism/ID in public schools)
In fact, I can deffinetely say that I have only had one leftist teacher in my education so far.
Most of my history teachers have brought up the idea that socialism is evil and bad in practice (Always citing the USSR as the example).
When I was in 9th grade, my biology teacher brought up the idea that evolution could be false. (A blatant lie at that)
Why are there dumber teachers in the system?
Simple.
Look at the link that corplinx provided above:
http://www.gmu.edu/departments/economics/wew/articles/04/ineptitude.html
I would say I have to agree with this article.
No Child Left Behind has the right idea, as in the fact that the teachers that are to be hired, have to have a degree in the field that they are teaching.
No Child Left Behind has these two faults that make it punish the public school system:
Cuts funding out of districts that are already poor, because of bad test scores.
Teachers that were/are going to be hired need to have a Masters in Education along with their specialty degree.