Luckily, most Chromebooks come with unlockable bootloaders. That's not really the problem. I worked at a coding after-school program. We had a bunch of Chromeb

Luckily, most Chromebooks come with unlockable bootloaders. That's not really the problem. I worked at a coding after-school program. We had a bunch of Chromebooks which worked fine, but were no longer receiving security updates. Since all coding teachers need to be moderately technical people, I briefly considered installing some lightweight Linux distro. I then immediately discarded the idea, because I was absolutely not going to install Linux by hand on upwards of 30 Chromebooks, plus deal with supporting them in the future. A real school would have much more than 30 Chromebooks. Admittedly they might also have a dedicated IT staff for a project like this, but I bet it's still more economical to just replace the computers. (Which doesn't necessarily mean they can afford either of these things.)