Dunno what made me think of this just now. When I worked for IT in a school district way back in the 90s, a librarian told me she kept a supply of mouse balls in her desk because kids would steal them out of the school computers. What I remember about those balls was they picked up dust and crud off surfaces. Pretty soon optical mice came along and they were history.
Can’t believe I had to scroll this far to find this. Looks like my school and yours were the only two in the world where it occurred to anyone that you can just superglue the door shut to stop the little shits from thieving them.