On a RPi, with a standard laptop on the side (Windows/Mac/Linux, doesn't matter), and some basic installed tools, you can pull down and configure Alpine Linux and run a bare bones IoT Linux platform. If you want to get really gritty, you also configure and build U-Boot as a primary loader.
Once you get passed that point, you pull docker into your Alpine build and start running containers.
Stepping through that full process will teach you research (because you are going to be reading a lot about how to pull that off), it will teach you about Linux kernel configuration. It will teach you to be at least comfortable with git.
There is a lot you can learn on a Raspberry Pi, cheaply, that only involves plugging in an ethernet port and power supply, and never seeing anything on a terminal.
I also doubt that raspberry pis are actually the type of device that schools are interested in. What they'd want is the TI-84 equivalent of a laptop. It should be easy to reset the laptop to factory conditions and it would only run a few specific preinstalled programs (one of which would be a barebones IDE, probably for Java). To me it feels like the raspberry pi fails at all of these. You have to mess with hardware and then mess with the software. A school provided Chromebook with student accounts managed by the school would be way more practical.
However, if you actually want people to learn programming organically, it's much simpler to just get a Windows laptop and use that as the main device.