It's so depressing to read stories like the one on the unhinged geography teacher using his Colorado classroom as a pulpit to preach his anti-American message to his captive audience. Michelle Malkin has the transcript of the tape that one disgusted student made of the teacher's rantings plus links to the podcast of the tape.
I don't believe that it is possible for teachers to totally keep all opinion out of their presentations. To me, it's similar to the media's claims to be totally neutral. Where the bias comes in is with what material the teacher chooses to present. You can't cover everything and if you choose to cover some material and leave out other material, your biases may well color what choices you make.
At least, however, teachers (and journalists) should try as much as possible to present both sides and let kids make up their minds. The way that this teacher goes on a rant about how the U.S. is the most violent country on earth and Bush is using some of the same techniques as Hitler is just beyond the pale.
Some people are upset about the idea that a kid would tape a teacher and then release the tape to the press. As a teacher, I'm aware that the kids can go home every evening and tell their parents everything I said in class that day. And, being teenagers, they might run my words through their own prisms of reality. At least, this kid has the tape rather than just his own hearsay. We can judge for ourselves and there is a long enough transcript to get the context of what the teacher was talking about in class. Teachers shouldn't say anything that they don't want the public to know that they said in class.
After all, as a public school teacher, I'm an employee of the public. I treasure the opportunity to work with these students and take that responsibility very seriously. It really grinds my gut to hear about a teacher who abuses that responsibility. I would like to believe that such a teacher is the exception.