I'm not presuming anything was installed on school computers. Did I say that? I'm only assuming that some sort of computer is being used for coursework of some kind - presumably it's the kid's computer. I'm just saying, I can understand why the teacher would be annoyed if she feels like she has to deal with Linux support issues and she's not trained to do that. Obviously her reaction is over the top, but I can also imagine why she would be annoyed. Heck if I had a room of 30 kids asking me anything I might start sending illogical, angry letters all over the place.

I love Linux as much as the next geek, however, I can sort of understand her point of view, even if she doesn't represent herself very well. If a kid wants to play with Linux and learn about how the computer works then s/he should do it, but if it prevents the computer from working properly with coursework or software provided by the school, then that could be a problem. I can see how it would be highly annoying to a teacher, who really has better things to do than to support PCs, to have to explain why some document won't display properly, or something won't work exactly as it should on Linux. In a setting where spending any time at all on helping kids with how their laptops work is a huge distraction I can see how encouraging students to install Linux would be a very big disruption. Some will disagree, and it's better than it used to be, but I still wouldn't advise my mother to replace Windows with HeliOS or Ubuntu or any other Linux. The reason people choose Mac and Windows isn't entirely marketing and bundling, it's also because they tend to be easier to get support for - or even for novices to figure out.