Children are scared to go to a school run like a "military boot camp" because of a teacher known for his strictness, a parent claims.
Stowupland High School brought in Barry Smith after a "requires improvement" Ofsted rating in December.
But one parent said others were thinking of moving their children due to Mr Smith's appointment.
The John Milton Academy Trust, which runs the school, said Mr Smith was supporting staff.
Mr Smith was previously the head teacher at Great Yarmouth Charter Academy, and was known for "army like" strictness which was criticised by some parents.
He introduced a 22-page rules guide - which included setting a 21:30 bedtime.
During Mr Smith's tenure, the Norfolk school - rated "inadequate" by Ofsted in April 2016 - was judged to be "good" in July 2019.
During an Ofsted inspection in December inspectors found pupils at Stowupland High School were "unsettled" and their behaviour had been affected.
Parts of the school are also closed due to the presence of Raac, which has led to parts of the site being closed.
Rachael Alexandra, whose son is in Year 8, said the school wrote to parents about "light changes" following the Ofsted report.
However, she said there was a difference between light changes and "installing someone in the school with incredibly bold views and, in my opinion, scaring some of the children."
She said: "I understand there have been problems with some children's behaviour but it's not every child and every child is being treated in a very odd manner.
"My son has gone from being a really enthusiastic, bubbly child to not wanting to be at school.
"Yes, behaviour should be right but I don't send my son there to feel like he was in a military boot camp and terrified of not making the right eye contact.
"And terrified he'll get detention if he doesn't say the right thing at the right moment," she added.
Talking to other Year 8 parents she said it seemed like many were considering moving their children to another school.
She said she and other parents had written to the school - but not heard back.
A spokesman for the John Milton Academy Trust said they had brought in several people and organisations in light of the recent Ofsted report to "enhance the learning environment" - including Mr Smith.
"Mr Smith has been working with the Trust to support staff in encouraging students to buy into the school's vision, ethos and expectations for behaviour as part of this improvement programme," he said.
