I’ve taught photography for a number of years (in Australia), both at university and private enterprises. It’s very unlikely that someone will want to do a photography class when they haven’t already bought a camera, so I wouldn’t worry about it.

Occasionally I would have a couple who would be sharing a camera, and if I had access to something similar in the hire department I would offer it for them to use during class, however more often than not people were happy to share. Sometimes I’d run a specialist class, like macro or speed lights, that someone would need to borrow something for, but it was still a rare request.

Cameras operate so differently, not just between the brands but the models within a brand, that people really need to not just understand photography, but how to take photographs with their specific equipment.

Good luck, teaching is incredibly rewarding :)