New teachers often have a wobbly introduction to the classroom, but John Owens' school baptism resulted in his being threatened with arrest and plagued by lesson observers wielding stopwatches. He quit after just five months.
It was such a challenging period of his life that he decided to write a book about his experiences, which is now making waves in his native US.
Confessions of a Bad Teacher: the shocking truth from the front lines of American public education lifts the lid on the data-driven world of high- stakes testing in US schools, which has strong parallels with teachers' experience in the UK.
After 30 years in the magazine publishing business, Mr Owens decided to change career to give something back to society. After seeing an advertisement for teaching on the New York City subway, he took the plunge.
He completed a year of teacher training in graduate school and then landed a job as a writing teacher in a reform school in the South Bronx, one of the poorest districts in the US. The school had been established by the office of Michael Bloomberg, mayor of New York City at the time.
From there, things started to go wrong for Mr Owens. "(It was) like a charter school, but it was called a college preparatory academy. So the kids had to wear uniforms - we had a lot of this Harry Potter stuff going on," he told TES. "You had to keep the kids quiet so that if anyone walked in it looked like a cathedral of learning. I called it a pageant: we were pretending it was a school where kids were learning."
It didn't take long for the new teacher to make an enemy of the principal, but the situation worsened when he turned down an offer to attend a training seminar in New Jersey - he wanted to stay with his students to give them "stability".
"I was labelled as a lazy person and suddenly I was a bad teacher," he said. "I had people in my classroom constantly evaluating everything I did. They would sit there in the classroom and if anyone talked out of line that was your fault. We had the lessons broken out into segments and I had my supervisor in my classroom with a stopwatch. They would stopwatch each segment of the lesson."
The main reason Mr Owens wanted to go into teaching was his own positive experience of education in New York, but he said that the differences between school life then and now were stark.
"Today it's all about the data - they have allowed the spreadsheet to hijack the educational system," he said. "So what you have to do is make it look like the students are learning, then on a spreadsheet prove they're learning.
"We would collect data on anything. It wasn't just quizzes or tests or homework: it was also things like what they called the core values of the school. They would grade them on things like `unity of being' and `reflective living' and `self-determination'. I have no idea what that is but some of my kids did very well in it."
According to Mr Owens, the focus of US public education has swung too far towards academic concerns, to the detriment of everything else. He began to feel disillusioned, and his situation became critical when he implemented some old-fashioned discipline.
"I tried to keep my eighth-period class behind after school one day for 10 minutes, so I wouldn't let anybody in or anybody out," he said. "(The principal) considered it corporal punishment and she threatened to have me arrested. To be arrested in the South Bronx, you have to do something pretty heinous.
"I kept going for a month or two after that. I was hoping to be able to redeem myself. But the problem is that, when you're a beginning teacher, if you get a U for unsatisfactory for the whole year you can't teach again in the city. So they try to hang that over you like the sword of Damocles, because if you get a U your career is over. My career was definitely going to be over. I was definitely going to get a U."
After five months, Mr Owens resigned and wrote an article for US magazine Salon. It was so well-received that he decided to write a book. He said he wanted to "expose" what was happening in the country's public schools and give a voice to teachers whose grievances so often went unheard.
"People like Bill Gates and (the former) Mayor Bloomberg all have this notion that education can be done very efficiently. But I think education is a lot like marriage and other good things: education is sloppy. Kids are not widgets," he said. "So that's what I wanted to do with this book: to show school reform, and how it's failing, and why it's a con and it's bogus. Why I think it's an insidious cultural development."
Confessions of a Bad Teacher: the shocking truth from the front lines of American public education by John Owens is published by Sourcebooks.