California NAACP seeks to remove 'Star-Spangled Banner' as national anthem
California NAACP Denounces Star-Spangled Banner as Racist, Anti-Black People
California NAACP Wants To Remove Racist Star-Spangled Banner
The excerpt in the last thread (my order here is simply chronological) explicitly identifies the Offensive Section as the same part of the third verse.
I wouldn't be at all surprised if this action at the high school comes directly or indirectly from the California NAACP effort (or if both come from the same deeper parent source).