Teachers and parents have voiced their anger at a primary school test that was so tough it left children in tears.
The Key Stage Two English reading test sat on Monday by pupils aged 10 and 11 was criticised for being so difficult it risked demoralising pupils.
One teacher branded the test "ridiculous" and "divisive" as the advanced questions also risked alienating children whose parents did not support their education at home, or those for whom English is not their first language.
Parents said their children struggled to answer questions or finish the test after doing well in previous years.
At least two primary school head teachers are reported to have written to their pupils telling them to be happy with their achievements regardless of their results.
One headmistress at a school in Kent reassured her pupils: "The people who create these tests and score them do not know each of you in the way we do."
Nearly 600,000 year six pupils are understood to have taken the English reading test.
The exact contents of the Standard Assessment Test (SAT) cannot be reported until May 20, although that did not stop teachers flooding on to the TES forum to share their views on the questions and share their pupils' reactions.
One wrote: "Ridiculous. Very difficult. The 'easy' text was harder than the most difficult ones of previous years. The nuances and depth of language across the texts baffled many.
"A very divisive test. Those with EAL (English as an additional language) and those for whom high quality language isn't present at home utterly floundered."
Another contributor said they were fearing the worst after the "tough" test.
"I can't believe how many of my kids didn't even manage to finish the paper. The texts weren't so bad but the questions and the wording of them (vocabulary etc) was like something I have never seen before. I'm staggered."
Others said it remained to be seen how the test would be marked, but some said they were concerned that pupils may be left demoralised.
A number of parents shared their concerns on a Facebook page belonging to Education Secretary Nicky Morgan.
Alison Escritt said her son was a passionate reader, but had been left feeling "fed up and demoralised" by the test.
She wrote: "The incompetence of your department beggars belief. How dare you make my child, a bright and gifted learner, feel like he has failed."
Kirsten Burns said: "Reading test today has left my bright Y6 child who is a prolific and mature reader upset and worrying because she couldn't get to the end of the paper and found 'most' of the questions 'hard'. Challenge is good, too much challenge is paralysing."
Another parent wrote on Mumsnet: "My son was in tears halfway through and didn't finish it. He's a bright boy and very eloquent but reading has never been his thing. He's so dejected after today."
Ahead of this week's tests in English and maths, Jennie King, head teacher at Willesborough Junior School in Ashford, Kent, reportedly wrote to her year six pupils praising them for their work this school year.
She said: "The levels that you will get from these tests will tell you something, but they will not tell you everything. There are many ways of being smart."
Meanwhile Joseph Allen, head of Holy Trinity primary in Rochdale, is understood to have told his pupils to "relax and chill" as the tests were "not the most important thing in the world".
A Department for Education spokesman said trials showed the difficulty of the test was "broadly similar" to samples handed out earlier this year.
They said: "These tests should not be a cause of stress for pupils - they help teachers make sure children are learning to read, write and add up well. The truth is if they don't master literacy and numeracy early on, they risk being held behind and struggling for the rest of their lives. We are determined to prevent this by helping every child reach their full potential."