I actually went to this school when I was younger (so I was pretty surprised to see it appear on Slashdot!), and was very interested in this article because when I was there, we were given a very good IT education - in MS Word, Excel, Access, Powerpoint and Frontpage (plus, er, PageMaker).
Anyway, I think there are a few reasons why this userbase might adapt to Linux better than a random selection of people:
1. Their age - while a lot of older people are extremely reluctant to just try something on a computer, for fear of breaking it, people who've grown up with computers as the norm aren't so worried about that. So I think they're less likely to be intimidated by a new interface, and more likely to engage with customising it.
1a. You would also probably get less resistance from them than from a worker who's been using MS Office every single day for the past 20 years and is extremely familiar with it and therefore works very, very quickly. Swapping their software over will result in an immediate productivity drop and could cost a company money. Swapping a 12-year-old's software over is a minor annoyance.
2. It's a science and engineering school, so a number of the girls who have chosen to go there will have a bigger interest in technology than the average population of the area. (There are other schools of a similar academic standard locally with different specialisms and this does guide some students' school preferences.)
3. The school is academically selective, so you have a better chance of being able to teach the students how to adapt to different systems (swapping between Linux and Windows when a workplace requires it, for example). In an average population you will confuse a lot of people just because the blue "e" they click to go on the Internet has disappeared.