What’s the standard protocol for a student threatening gun violence at a school?

I was told by about a student who was expelled from Coconut Palm K-8 Academy for posting a handgun on social media and threatening to use it to shoot another student. The student was sent home but there was no legal involvement or actual repercussions.

I didn’t go to school down here so is this how the situation is typically handled? None of the other parents were notified as far as I’m aware and I’m trying to figure out if that was intentional to prevent inciting fear.