And there's nothing wrong with that. Kids will be more productive on Windows and more likely be able to take those skills with them. How many kids need to know linux in the future? Here's what the Linux trend looks like: http://www.google.com/trends/explore#q=linux
'linux' is a single keyword, while GNU/Linux OS might show up as a wide set of different keywords, like ubuntu, debian, mint, arch, centos, rhel, fedora, gentoo, opensuse. Note that this is not the case with Windows, iOS, OSX. So, it would be interesting to see the combined interest of all those added to that of 'linux' for a more correct perspective - not considering Android of course, since it's not a GNU/Linux system.
BTW it seems interest in Windows is also halving every ~10 years (though not as fast as 'linux'):
Edit: I was partly wrong; the matter is much more complex than that: interest in iOS and OSX might show up as interest in iPhone/iPad, and Mac/Mac OS; interest in Windows, besides any interest in 'surface', might also show up as a generic interest in 'PC' or similar terms: you can make such assumption, since anyway those interested in 'linux' or 'OSX' would probably avoid using terms generally associated with Windows.
Sorry, and it pains me to say it as I'm the patriarch of an OS X family, but: Kids. Their first exposure to computers will be at home. And it'll therefore likely be Windows. My kids don't know Windows, they know OS X and iOS. Sometimes, after they've visited friends, they comment that they played on a computer that "looked weird", but they've never had a problem adapting.
It's that last bit that seems to suggest a "who cares what the OS is, kids don't care" idea. In my view, though, it really doesn't. Kids aren't known to have a higher order of executive function. They'll generally just use whatever the trusted adults in their lives use.
Those trusted adults should be exposing kids to all the options, so that the kids are better prepared to make decisions when their executive function skills catch up.
Was this weird computer they used a Windows machine or was it an old OSX version? :-)
Only kidding. I went to PC World the other day and attempted to use one of the Windows PCs and quickly became angry with Windows 8.1. Seems I have been using Macs for too long (and I used to use Windows daily, now I do but in a VM and it pains me).
Is it not more productive for teachers to teach something they know? If a kid has a question about Linux and the teacher doesn't know Linux, they won't be able to answer the question. Likewise if a kid has a question about Windows and the teacher doesn't know Windows, they can't answer it.
It doesn't matter what system it is, teachers are best at teaching what they already know.
I didn't say "should only teach". If your (obvious facetious, I know that) argument actually followed mine, it would say "A teacher only knows DOS, they would be most effective at teaching DOS". Which is true.
The point, though, of the parent commenter was that just because a teacher can teach something "effectively" doesn't mean that something should be taught in the first place.
There are plenty of teachers throughout the United States who are effective at teaching creationism to their students. I think we can all agree that doing so is not healthy for those students.
All of them, if they want any hope of having a programming or system administration job (i.e. the non-executive IT jobs that pay pretty darn well) in the foreseeable future. Linux is what powers the vast majority of web servers nowadays, regardless of whether they're being run by plucky startups or long-tenured industry incumbents. Windows in the server world has effectively been relegated to legacy systems and a smattering of government websites (some of which in and of themselves also count as "legacy systems"), and that market is continuously shrinking as businesses modernize in methodology and technology.
