And just for the record, no it wouldn't be illegal for her to have recorded it regardless:
"Conversations in private places are banned from third party audio recording and a member of a conversation can covertly record the conversation without the consent of others. Conversations that occur in public can be recorded by a third party (see O.C.G.A. § 16-11-62).
Recording actions in public places without the consent of those being recorded is legal. Recording actions in a private place or in a public place that is out of public view requires the consent of all those being recorded (see O.C.G.A. § 16-11-62). The law has further clauses regarding recording actions of individuals under 18 as well as when it is on one's own property.[1]" ~
Georgia (U.S. state) wiretapping laws - Wikipedia, the free encyclopedia
Schools are considered "public" places so that's that.