In the comments, I was asked my thoughts on chromebooks vs Linux on low end hardware so, here they are.
Chromebooks are cheap, near instant on, and, if you're using Google Apps for education, little to no administration necessary.
This is a HUGE win for schools.
There are some issues. School WiFi, for example, is frequently insufficient which can be a problem for a device that's meant to be connected to the cloud. People might think that schools are well connected but I know multiple schools that keep kids off the WiFi to keep it from being overloaded. This is a problem and I don't know if it's really being addressed.
It's also worth noting that DOE pricing is also a far cry from "lowest bidder." We keep seeing sub $200 chromebooks on the market but buying through the DOE approved vendor looks to cost about $300 per unit or more. Of course this is better than the equally inflated PC/Mac prices.
Still, the price and easy of deployment and administration seem to make chromebooks the way to go.
As to other issues, first, you have to buy in to the Google platform – email, docs, classroom, etc. This isn't necessarily a problem. I personally like most of Google's offerings. My big concern is giving away student data. I have mixed feelings on the whole privacy thing but it's more clear cut when it comes to minors in public schools - schools shouldn't be sharing their data and schools shouldn't be forcing them to share their data. Google Suite for Education is FERPA compliant but what about all the other Google services the kids might be using? I haven't looked at this carefully but we've already given too much power to private interests over education (see the College Board or Pearsons) so, at least to me, this is a concern.
My only other issue is a selfish one. As a CS educator, I look to coding tools and environments. While there are online platforms like cloud9 or repl.it, they don't have the same power and flexibility of using local installs. I've been using repl.it and it's a great tool but I think it's best used as a stepping stone to a local install and then afterwards for some of it's specific value added features. I'm also a big believer in teaching operating system as tool box, something you can't currently do with a chromebook.
Willy Karam commented over at AVC about using cheap hardware running Linux. This is something I've done for years and it's been a lifesaver. CSTUY's entire laptop collection consists of really old laptops running Linux.
For a CS class, this works well. Even for a non CS class it can work well. Modern Linux distributions run pretty much the same as Windows and MacOS. Use the mouse to click on menus and icons. It doesn't give you the power of the command line but it means it's a suitable alternative for the masses that use the operating system as a program loader..
The downside of Linux for the general population is the administration and maintenance. At Stuy, we set up NIS and NFS. Both horrible but probably easier and better than most alternatives. I was never able to come up with a better way to do authentication and file sharing and the NFS stuff would have killed our wifi (we only used it in wired labs). Customizing software installs is also a real problem. We made it work but it took far too much time and effort.
If you're in a situation where you can do a stock install and then give the machine to the student for the semester, then Linux can work really well. If you're talking about shared machines with custom installs, it's harder to justify over chromebooks.
A final note on chromebooks is that last year, I played with putting Linux on a chromebook. It worked pretty well. Almost the best of both worlds. Low end hardware with good battery life and a full operating system. This is something I have to play with on the current generation of chromebooks.
So, where do I stand on this? The cloud isn't there yet in terms of teaching computer science. It's fine for a gentle introduction but eventually, you'll need the power of a full blown OS and local installs. We may very well get to where a cloud OS is just as expressive, we're just not there yet. On the other hand, for general computing in schools, chromebooks are a big win.
It would be wonderful if schools had sufficient infrastructure, support staff and training so that technology was just there and just worked and we didn't have to make these sort of decisions and compromises. Somehow I don't thing that will be happening any time soon.