A primary school teacher has written a resignation letter to the Secretary of State for Education, accusing the government of having “obliterated” the education system.

Zoe Brown, an assistant head teacher at Farnham Green primary school, Royal Close, Seven Kings, said it was “with a heavy heart” she would hand in her resignation letter following growing pressures on school staff to achieve results rather than teaching pupils life skills.

She published the letter addressed to Nicky Morgan and called Sorry, Nicky, I’m out, on her blog The Girl on the Piccadilly Line.

The young teacher who has been in post for six years explained she was no longer proud of having joined “the noble cause” of teaching but was only preparing her pupils to pass exams, while sacrificing anything that was not English and Maths.

Miss Brown was teaching Year 2, when pupils are now expected to sit the new SATs exams, which she described as the “greatest challenge to date”.

The new tests combined with data-focused school inspections, more complicated Ofsted guidelines for assessment and frozen pay was the tipping point for the primary teacher.

“In some ways I don’t feel like a teacher at all any more. I prepare children for tests and, if I’m honest, I do it quite well. It’s not something I’m particularly proud of as it’s not as if I’ve provided my class with any transferable, real life skills during the process.

“They’ve not enjoyed it, I’ve not enjoyed it but we’ve done it,” she wrote.

Miss Brown’s letter comes after parents took their children out of school on the day of the SATs exams earlier this month to protest against what critics perceive to be a new exam-heavy curriculum.

In the letter, she said she knew the job would be “bloody hard work” from the start, working about 60 hours a week in the classroom, preparing classes, worrying about results and individual pupils’ lives, she explained.

But she did not expect the job to get any harder.

“It eats into the rest of your life both mentally and physically,” she wrote.

She also warned cuts to school budgets, shortages of staff and the hiring of unqualified teachers to fill the gaps were “the final nail in the profession’s coffin”.

“Just within my own family my fiance, my sister and my sister-in-law have all quit the profession in the last 12 weeks,” she added.

Miss Brown is expected to finish the academic year at Farnham Green. The school declined to comment.

A spokeswoman from the Department for Education said: “It is disappointing to hear of any teacher choosing to leave the profession, and we will respond to this letter in due course.

“But we make no apologies for our reforms that are giving more children than ever before the best start to life. Thanks to the hard work of teachers there are a record number of children in good or outstanding schools – 1.4 million more since 2010.”

The full version of the letter can be found here.

Read the teachers’ union reaction claiming “the soul of teaching has gone” here.