School inspectors are writing to children as young as four saying they may fail in adult life because of the way they have been taught.
The letters - sent out following inspections - feature dire warnings that they may fail economically as a result of their schools' failings.
Teaching unions and education groups this week demanded that the letters be scrapped.
One letter from Ofsted - signed Her Majesty's Inspector - to children at a Nottinghamshire primary included the stark warning: "You are not well prepared for your next stage of education, nor your future adult lives."
Another letter told pupils at a London primary that they would need to become better at writing and maths to help them get jobs.
The letters, written in simple English, have been controversial since they were introduced in September 2005. Schools are legally obliged to send inspection reports to parents - and included are the letters to pupils.
Ofsted insists most headteachers support the letters, which often suggest to children that teachers are to blame for their poor work.
The letter to pupils at the Nottinghamshire school added: "We think the school doesn't do enough to help you to do your best and so you don't learn as much as you could, especially in reading, mathematics and science."
Others letters suggested that teachers were to blame for lessons not being sufficiently enthralling or challenging.
"I have asked your teachers to make sure that lessons are more interesting," one inspector wrote to pupils at a Cheshire school.
Chris Keates, general secretary of the NASUWT, said the letters should be scrapped because they were "ridiculous, unnecessary and ill- conceived".
"To cater for their target audience, these letters often over simplify the outcomes of inspection and in doing so misrepresent the findings," she said. "The letters in effect give license to pupils to question the professionalism of the school and its staff.
"There is no evidence to show that they serve any useful purpose. They should be scrapped."
Margaret Morrissey, of the National Confederation of Parent Teacher Associations, said families did not see why children needed the letters either.
"They are unhelpful and can just make some precocious children even more precocious," she said. "A 10-year-old might switch off because they no longer respect their teacher."
Ofsted asks each school to fill in a survey after it is inspected. A spokeswoman said that responses to the questionnaire between April and June this year showed 86 per cent of headteachers felt the letters to pupils were a useful way to inform them of inspection findings.
"Other surveys also indicate that, where schools involve their pupils in sharing the key messages of the letter sensitively and openly, they are a valuable tool in engaging pupils in both the inspection and subsequent school improvement," she said.
An example of an Ofsted inspector's letter
Inspection of ********
Thank you very much for making me so welcome when I visited your school recently to find out how well you are learning. You told me a lot about your school and that helped me to decide what the best things are about your school and what needs to be improved.
Most of you say that you enjoy school and have good friends. You are good at knowing how to be healthy and make sensible choices about your food, as well as participating enthusiastically in many sports activities. This is excellent for your growing bodies and physical well-being. Well done!
However, there are a number of things which I am concerned about at your school and as a result, I have asked your headteacher and teachers to improve these things for you. You are not reaching the levels you should in English, mathematics and science and this means you are not well prepared for your next stage of education, nor your future adult lives. Some of the teaching you receive is too slow and you spend too much time listening to the teacher instead of practising the skills you are learning, through exciting, purposeful activities. Some of you talked to me about your targets for improving your work, but many of you are unsure about your targets and how to meet them. Finally, your headteacher needs to be clear about what the school does well and what needs to be improved, so that the correct action can be taken to put things right.
Over the next few months everyone will be working very hard to put things right. You can help by behaving well in class and making a big effort to improve your work, especially your writing. Inspectors will be coming back to check that your school is improving. I would like you all to work hard and help your teachers make ********* a better school. I wish you all the best for the future.
Her Majesty's Inspector
Pointing the finger at teachers
Quotes from a selection of letters.
"We decided that the school needs to be helped to improve as a matter of urgency. This is because the school is not providing an effective enough education and most aspects of the school's work are not good enough."
"We think the education you receive in Years 1 to 6 is not good enough."
"Unfortunately, we found that you are not learning enough. Lots of the work is too easy for you."
"The quality of teaching is not good enough. I have asked your teachers to make sure that lessons are more interesting."
"You need to improve your writing and maths skills to help you get jobs when you are older."
"The people in charge of your school and your teachers are not making sure you are learning as fast as you can."
"Too many of you are not doing well enough in English and mathematics to help you to do as well as possible in the future."
"Unfortunately we found that your school is not as good as it used to be or as it should be now."
"You try hard with your work, but too many of you are not doing as well as you should because not enough is expected of you."