One in 10 secondary school children do not have home computer access, according to a survey, and it is likely that the 10 per cent of homes without computers are among the most impoverished.
The survey by Kirkland-Rowell, a school self-evaluation firm, shows that marginally more girls than boys have home computers.
Egglescliffe School, a comprehensive at Stockton-on-Tees, Cleveland, has completely turned around boys' under-achievement after investing heavily in computers. Boys there who trailed 12 percentage points behind girls at GCSE have now overtaken them.
The reason, says Brian Lockwood, head of ICT, is that boys are motivated by technology.
At Egglescliffe, boys are now getting involved in subjects that were traditionally seen as "girly", such as art, music and drama and with intensive use of technology in those subjects, they are performing well.
Computer technology is now seen as key to getting boys excited about learning and helping them catch up with high-achieving girls.
But Egglescliffe is in a prosperous area, where only six of its 1,450 pupils are without internet access at home. "In one of those homes the parents think the computer is the devil incarnate and they'll never have one in the house," said Mr Lockwood.
The Kirkland-Rowell findings coincide with a report from Becta, the education technology agency, which says that girls are more likely to use computers at home for school work.
Becta's Harnessing Technology report, found that more than 90 per cent of teachers believe computers aid boys' motivation, and more than 70 per cent believe computers improve their attainment.
More than half of secondary teachers set homework that required internet access, it said.
Mark Chaplin, managing director of Kirkland-Rowell, said access to computers and the internet was recognised as a very important tool in enthusing boys to learn, and in closing the attainment gap.
"It is worrying to see that there is still a persistent 10 per cent of secondary pupils who have no access to computers at home," he said.
His firm surveyed 30,000 pupils in 2004, and another 75,000 this year. It found this year that 90.5 per cent of pupils had computers at home, a figure almost unchanged since 2004.
Home computer and internet access are critical to the Government's 2008 target for every school to provide an online learning platform for pupils, parents and teachers.
Last year, the Government announced pound;60 million funding over two years to provide computers for children in the poorest 10 per cent of households. That begins rolling out this term, as the London Grid for Learning provides more than 10,000 computers, mainly wireless-enabled laptops, to poorer children in the capital.
Brian Durrant, the Grid's chief executive, said the 10 per cent of children still without home computer access was a major concern, both for them and their families' participation in the community.
"It is very important that economically disadvantaged children should not be further disadvantaged in their life chances by being denied access to continuing personalised learning outside of school," he said.