A headteacher has backed down over plans for a wildcat boycott of the key stage 2 Sats tests next week because he could not find anyone to join his unofficial campaign.
Former test marker Wayne Howsen has reluctantly called off his boycott because he feared he would "be made an example of" by the authorities if he decided to go it alone.
"I'm not prepared to lose my job over this," he told The TES.
The head of St Catherine's C of E Primary School in Hoddesdon, Hertfordshire, said he had lobbied heads locally and nationally to join him, but most said they had decided to "trust the Government" and its independent review by Lord Bew.
Mr Howsen, who earlier this year accused other heads of being "really weak and cowardly" for not standing up to the Government, told The TES: "After extensive lobbying, not one head has contacted me to say they feel the same as me. I was very surprised that not one head stepped forward to join me.
"I wanted there to be at least a handful of people with me; we could have made a lot of noise. I thought I would have safety in numbers. But on my own ... I could lose my job."
Mr Howsen's governors have supported him in his plans to boycott this year's Sats, although the chair and vice-chair of governors resigned, concerned about possible legal ramifications, according to Mr Howsen.
During the last Sats boycott in 2010, which involved around a quarter of primary schools in England, many heads expressed concerns over the legality of the action.
He said many parents at his school had talked about organising their own Sats boycott this year, but he "talked them down" because he could not encourage parents to take their children out of school.
However, a motion at the recent NAHT conference has offered Mr Howsen a ray of hope.
Delegates voted to consider another boycott if significant changes to the testing regime were not in place by next year.
Proposer Steve Iredale, vice-chair of the union's assessment reform campaign, said that although pension reform now topped the political agenda, they remained focused on Sats.
"That does make me feel more positive," said Mr Howsen. "Sats should still be number one on the agenda because nothing has changed since last year."
NAHT general secretary Russell Hobby, who called off a vote over whether to boycott this year in exchange for Lord Bew's independent review of testing, said of Mr Howsen's decision: "I respect the strength of his feeling and disappointment but I'm glad he's doing what the rest of the association is doing."