I would suggest him to have a school wallet and accept school donations for upgrades/events/etc. in crypto, specifically in BTC. That's for a start. And if he sees fit, in time he can also accept school fees or a at least a percentage of the fee. That would be a great win. The issue I see here with the wallet being a school one is the security of the keys indeed. That is something that has to be fully explained and understood before anything. To be understood as I would not take responsibility with the keys