Make Reader the default for all users in Windows 10

I want to make Reader the default for pdfs for any user that might log on to a Windows 10 computer. I have 22 computers in an open lab, and each computer will have multiple (and different) users each day, so setting the default for each user is obviously not feasible, and setting it while the administrator is logged in of course doesn't work. Users are not administrators, so even if I provided instructions they could not set it themselves. I would love a registry hack, or something not terribly involved as a solution. Any solutions?