Boys in Northamptonshire are less likely to pass important Year 1 reading tests than girls, new figures show.
Department for Education data shows the results of phonics tests, which children take aged five and six.
Children sound out a series of specially created words to show they can read the letters rather than just recognise words. If they fail they repeat the test in Year 2.
In Northamptonshire, in 2018, 86% of girls passed the tests, compared with 79% of boys.
The National Education Union believes this could be due to how boys interact.
Nansi Ellis, assistant general secretary of the NEU, said: “The answer might be in the quality of boys’ social interaction in early childhood, contrasted with girls’.
“Social interaction develops language skills, which in turn contribute to learning.
“This suggests that the answer to improving standards lies not in more formal teaching at an early age, but on improving children’s social skills through creating sociable and child-friendly classrooms.”
Disadvantaged children on free school meals have a significantly lower pass rate than those who do not qualify for them.
In 2018, 66% of children on free school meals passed, while 84% of other pupils did.
The National Education Union said these figures are “worrying”.
“Poverty makes a huge difference to educational attainment,” said Nansi Ellis, assistant general secretary of the NEU.
“Research shows that that children born into poverty have significantly lower test scores at age three, age five and age seven years.
“They continue to live in poverty in their early years and this has a negative effect on their cognitive development.
“Any serious strategy for raising educational attainment has to address these appalling figures.”
Overall phonics test scores have been steadily rising in recent years.
In Northamptonshire, 83% of pupils passed this year, compared with 55% in 2012.
Across England the pass rate has risen from 58% to 82%.
However, the NEU does not believe phonics tests help children learn to read.
Dr Mary Bousted, joint general secretary of the NEU, commented: “In prioritising synthetic phonics above other approaches to the teaching of reading, the Government is doing teachers and children no service.
“Schools are working hard to ensure high scores in the phonics test, but teachers have no faith that a relentless focus on one kind of reading method produces readers who can enjoy and engage with real books.
“The Government continues to confuse accuracy in decoding words with fluency in reading. They are not the same thing, and Schools Standards Minister Nick Gibb’s claim that synthetic phonics is putting children on track to be fluent readers has no basis in research.”
Northamptonshire has a slightly better pass rate than average for the East Midlands which is 81%.
School Standards Minister Nick Gibb said: “We want every child, regardless of background, to have a high quality education. Reading and writing are the foundations of that education.
“Since the introduction of the phonics check in 2012 there has been a huge improvement in the teaching of reading in primary schools.
“I remain concerned that 18% are not reaching that standard nationally and that 30% of children eligible for free school meals are not reaching the expected standard in the phonics check.
“Phonics is not dependent on the background of a child or on their cultural knowledge or vocabulary. It is a mechanical skill which if taught properly every child should be able to perfect.
“What this gap reveals is that in some schools phonics is not being taught as effectively as it should be. This is why we are establishing 32 phonics hubs, high performing schools across England that will work with other schools, including in disadvantaged areas, to improve the teaching of early language and reading.”