I think it's first of all up to school officials to refuse the FBI access to their school until they produce the warrant, UP FRONT, and explain what it is for in detail. Too many organizations capitulate in the face of such an organization and think of civil liberties second. I also think that school officials and parents ought to be complaining to their US Senators about such raids, applying political pressure to the situation. The FBI could have a valid reason for the search. That said, their tactics are one step short of fascist.