If the story about the "bomb-making teacher" actually happened as reported, then I would agree that he went too far.
But here in the land of terrorist paranoia and general fear/distrust of science, it would certainly not be unheard of for the media to blow an innocent chemistry lesson out of all proportion, and try to portray Pieski's classroom as some kind of al-Qaida training camp.
This guy wasn't just some maniac off the street. In fact, he was awarded the "Outstanding HS teacher of the Year" award the previous year by the American Chemical Society:
http://membership.acs.org/o/orlando/Awards/awards_banquet.htmNone of the numerous articles that were appeared offered anything from the teacher's POV, other than his statement in the police report. So there is no way of knowing what REALLY happened. All we have is the word of a couple of his students who got caught setting off homemade bombs, and a school administration who was eager to stop the negative publicity by firing the teacher.
Many of the demonstrations being talked about in this thread are potentially hazardous, and might be considered illegal if done outside the classroom. Sodium into water, acetylene balloons, detonating cans full of flammable gases, etc. are all essentially demonstrations of "bomb making". And with the internet, kids who want to build bombs certainly don't need a chemistry class demonstration in order to do so. But those who see such classroom demonstrations just MIGHT learn enough to keep from killing or injuring themselves in the process. The problem isn't KNOWLEDGE, it is people who would RESTRICT knowledge, out of fear about what *some* people might use the knowledge for.
The best demonstrations in a chemistry class are those that make a powerful and lasting impression on the students. And a small explosion is hard to beat in that regard.
Perhaps some of the growing lack of interest in the sciences among young people is due to the "sanitized" demonstrations being required in classrooms because of fear of lawsuits?
