They effectively blacklist under-fives by using a variety of tactics to put mums and dads off a school – and it's all because the heads regard some kids as undesirable.
The staggering claims were made by a serving head master at an influential forum.
According to a report in the Daily Mail, Nigel Utton, head of Bromstone Primary, Broadstairs, Kent, told the Westminster Education Forum, that pressure on schools to maintain test results was driving some to use dubious methods to keep out pupils considered disruptive or difficult.
"This is what some of my colleagues do across the country," he said.
"Basically they don't let them in. And there are different ways of not letting them in.
"One head teacher I know of puts Post-It notes on her wall.
"She goes round the nurseries finding out which are the disruptive children and puts their names up on her wall, and those children don't get into her school."
This head's school had been judged 'outstanding' by Ofsted, he said.
The school must abide by national rules on fair admissions so the head tries to stop them applying in the first place.
He also said parents were judged by what they did for a living. He claimed one head told a lorry driver that sending his son to the school would be similar to forcing him to work as a brain surgeon.
And he claimed that another common ruse was to 'alienate' parents at open days or show-rounds.
"When a parent comes and looks round your school, you are rude to them so they don't go to your school, they go to the school down the road," he said.
Mr Utton called on Ofsted and the Government to crack down on the practices and reward schools which do well with a broad intake of pupils.
His remarks received support from Children's Commissioner Maggie Atkinson, who is conducting an inquiry into ways that schools illegally 'exclude' pupils by asking them to leave without formally suspending or expelling them.
Speaking at the same event, she criticised schools which, at admissions time, tell parents 'we don't really deal very well with your child's needs at this school, but they do round the corner, so why don't you get them in there?'
"We have to do something about people who...would rather pull up the drawbridge and let children fail," she said.
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