The 1974 Federal Education Rights and Privacy Act (FERPA) defines access rights to educational records. The spirit of the law is to ensure that student records are handled with discretion and that communication about grades to anyone other than designated parties must be explicitly authorized by the student. For example, FERPA prevents an instructor from discussing a student's grades with the student's parents, unless a signed FERPA waiver is on file with the Registrar's Office.
More information about FERPA is available at
One important caveat is that FERPA does permit the disclosure of records (e.g., the discussion of grade information) with "school officials with legitimate educational interest." This means that it is permissible to discuss a student's grade information with the director of a program who inquires, with an athletic coach or administrator, or with a writing consultant, provided the "school official" has a "legitimate educational interest."