Cool school project. What is your goal to achieve with the kids?
Regarding your ‘HP ProDesk 600 G3 Desktop Mini PC’. I would install ‘Ubuntu Server’ it’s without graphical interface. The look and feel is like a ‘Raspberry Pi OS lite’ Installing Klipper with KIAUH. I have to admit, I never used a real Debian installation. I would prefer Ubuntu, because I think there is a much better support from the community (also Go+g*_e and what you may get). I’m sure your ‘HP ProDesk 600 G3 Desktop Mini PC’ will work with Klipper and ‘klipper.discourse.group’ will probably help you to get the printer working.
Good luck, hcet14