Also It is obvious to us people on the right that words like "harassment, intimidation, and threats of violence" never mean harassment, intimidation, and threats of violence when it comes to the right. They parents only threat would be to pull their kids out and home school them which is something conservatives have been doing on increasingly large numbers for the past few decades. Because schools are horribly leftist and some are even full on Marxist.
These are parents of children, not mercenaries. Demanding the schools stop teaching lies is not harassment or threats of violence. It may be intimidation but since when does intimidation warrant an FBI investigation.
This is clearly a 1st amendment violation. If you are a conservative you can no longer "...petition the Government for a redress of grievances" without being labeled a terrorist.