Your kids. Chromebook leads laptop and desktop sales through U.S. commercial channels to schools, according to NPD. Education is overwhelmingly the primary market for the computers. The institutions can’t buy enough of the thangs, for their utility and low-cost compared to notebooks running either OS X or Windows. That cost is as much about extended webapps and services from Google (or its developer partners), available for free or comparatively next-to-nothing, set against software for the other platforms.
Wrinkle in the Google firmament: iPhone and Chromebook are like water and dirt. The sediment settles unless shaken up. Sure youngsters can do all their Googly things—Docs, Gmail, Maps, Photos, YouTube, etc.—on iOS but the experience is smoother and more homogenous when mixed Android and Chrome OS. What the kiddies lack, and their educators, is a swath of useful apps like the Apple kids get.