"In the past four years, the members of the NFT have been subjected to an endless barrage of tactics from our elected officials," Ferrara wrote.
He said that a "small group" of members close to the leaders had conducted "terror and fear tactics in our workplace. Individuals have had damage done to their personal property, they have received written threats, and incidents of bullying during the school day.
"There is a significant amount of shunning led by none other than the elected president of the NFT," Ferrara wrote, referring to Louise Boyd.
Boyd could not be reached for comment Thursday. An NFT spokesman said the union did not comment on internal matters.
Ferrara also criticized the union's contractual right to have "equal say" in educational issues to block curriculum reform.
"The elected officials have openly insulted the members of our C&I [Curriculum and Instruction] department in the past and has had no educational reasons to halt many of the initiatives created by professional educators in our schools. Members who speak out to make changes in our delivery of content are ridiculed and so are those who support their ideas."
Webb said in a statement: "We want to reassure our valued teachers as well as our parents that we are taking all necessary precautions to ensure a safe, productive work environment in Neshaminy."
The teachers have been working without a raise for more than 31/2 years under a contract that expired in 2008. Their frustration led to an eight-day strike that ended last Friday.
Because of state-mandated arbitration following the strike, negotiations have been suspended, starting with Thursday's session, Webb said. Lawyers for both sides will meet to work out details of the arbitration, he said.
Contact staff writer Bill Reed at 215-801-2964, firstname.lastname@example.org, or @breedbucks on Twitter. Read his blog, "BucksInq," at www.philly.com/bucksinq.