My grandmother used to be Dean of Women at a small community college in bumfuck nowhere during the 70's. She told me about multiple "students" they had that were actually undercover FBI agents. FBI would come occasionally and ask if she could provide names of "troublemakers." She swore to me that she never ratted anyone out (I don't believe that personally), but said they would run names by her to see if she could confirm. Again, she claimed to play dumb, but she also said they knew every name she might have said.