I'm teaching children programming with Scratch and we're giving each student a Raspberry Pi to use. I want to be able to give them extra files for lessons down the road (like new background or sprite images), but I want it to be as seamless as possible. It's safe to say that their technical knowledge is low, so I'd prefer to have a background service do it automatically.
I use Syncthing for my own purposes across devices, so this was my first thought. But to prepare each Raspberry Pi, I'll simply be copying the same SD card image that I've prepared onto each student's SD card. My understanding is that Syncthing and other similar programs require unique user IDs for each system. So if I'm cloning the same system, they'll all have the same ID and I'm guessing this will not work as intended. But I also don't want to have to manually configure Syncthing across a dozen or more systems.
Is there some way to set this up before cloning the systems and have it sync files from my system to each of theirs without any action on their part? Alternatively, if there's some way to programmatically change the relevant files on the system image before writing each one, that would be fine, too. Thanks!