I think the author expects students to use programs like Safari and Microsoft Word with hundreds of man-years of polish by UI professionals. As a journalist, perhaps he is so lucky, but business people aren't. Business people have to configure generic software and use web apps slapped together by low-paid programmers who don't have the time or expertise to do good UI design. That can be very much like programming, unfortunately, and I can't think of anything else you could teach high school students that would prepare them for that task.