El Capitan folder permissions to make admin accounts read-only I have a folder with about eight sub folders which contain about seventy folders containing about 10,000 files. I want to give students read access to the files, but want to prevent them from accidentally or maliciously deleting the files. Although my admin account is listed as the "owner" of the top level folder and all of its sub-folders and contents, a student with an admin account of their own can drag one of these files to the trash and delete it by using their admin privileges. Is there any way to prevent this? Can permissions be set at a root level that would prevent deletion without running a terminal command?
No. Admin accounts can modify any ACL or permission you make to keep them out.


Admin = root on OS X


I would consider placing the files on a file server and control access over file sharing (where your account is the only admin) or remove admin permissions from the accounts that cannot be trusted to not be malicious or careless.