As many as eight out of nine schools in some local authorities remain without broadband internet access, despite the Prime Minister's promise to connect all by 2006.
Pupils face a lottery of access to high-speed internet connections. In 19 authorities, fewer than half of schools are equipped with broadband.
Figures released by Jacqui Smith, schools minister, show that only 11 per cent of schools in Reading and fewer than a quarter in Kirklees and Bolton have broadband access. By contrast, there are 39 authorities where all schools have broadband.
The technology allows many more pupils to have simultaneous access to the internet and is essential to download large programs, which would be impractical using standard connections.
Activities such as showing real-time events to pupils with an interactive whiteboard also require broadband.
Despite the variations, Ms Smith said the Government was on track to meet its target. Overall, three-quarters of schools, including almost all secondaries, are connected. This compares to only one in eight in 2001.
A Department for Education and Skills spokesman said variations were down to differences in local infrastructure and greater problems in connecting rural schools.