A grammar school's admissions test is "unfair" because it is biased against summer-born children, the Office of the Schools Adjudicator (OSA) has ruled.
The ruling followed an anonymous complaint by a parent against the 11-plus test run by Colchester County High School for Girls, in Essex.
The test put entrants born in July or August at a disadvantage, compared with older pupils of the same school year, the OSA found.
The adjudicator said: “A smaller proportion of summer-born girls who take the test achieve the required test scores compared to girls born at other times of the year. I consider that the admission arrangements currently in operation are unfair to girls who are born in the summer months.”
Results for last year showed that only 19 per cent of pupils born in July or August achieved a test pass mark for the grammar school, compared with 35 per cent of children who were born in September.
The OSA ruled that pupils taking the 11-plus test designed by the Consortium of Selective Schools in Essex (CSSE) must from now on have their scores adjusted to reflect age differences.
This test, which has been operated since 1997, is used by 10 grammar schools in Essex and is sat by 5,000 pupils every year, according to Comprehensive Future, a campaign group for fair school admission policies.
Campaign spokeswoman Melissa Benn said: “Critics of the 11-plus have for some time pointed out that the test assesses learning rather than ability.
The 11-plus 'should be phased out immediately'
“The adjudicator’s point on lower vocabulary levels confirms this, and is not only relevant to age. It equally applies to children from disadvantaged backgrounds and children who do not speak English at home, and therefore potentially opens the door to further complaints.
“In the past, the 11-plus was criticised for asking questions about domestic servants or classical composers, which might put working class pupils at disadvantage.
“Yet here we are in 2018 with schools testing children on passages from Dickens which may well advantage middle-class pupils who have these books at home. It is also wrong for 11-plus tests to cover maths concepts not taught in primary schools. These questions will be answered quickly by coached children, and attempted slowly, with little chance of success, by children who’ve had no extra maths coaching.
“There are so many problems with the 11-plus test and the selective systems that are built around it. It is the cause of systematic injustice and should be phased out immediately."
Grammar schools are currently permitted to design their own tests in-house, with no requirement to use professional test designers.
Comprehensive Future says it is unclear how many more of the 163 remaining grammar schools operate unweighted tests that may cause unfairness to summer-born children.