IANAL, but near as I can tell, it's still up in the air if (in the US) students have a constitutional right to be free of official retribution for off-campus sp

IANAL, but near as I can tell, it's still up in the air if (in the US) students have a constitutional right to be free of official retribution for off-campus speech. There is some evidence that if the speech is truly off-campus and if it doesn't cause a substantial disruption to school functions (see Tinker v. Des Moines), students are protected. Even the famous Supreme Court "BONG HiTS 4 JESUS" case was partially decided based on the speech being at a school-related event. On the other hand, "disruption" is defined rather loosely sometimes, perhaps even lowering the bar to content that is viral, as long as it is also insulting. See, for instance, SJW v. Lee's Summit.