Latest guidance says children should be protected from unsuitable material on the Internet. The decision has been strongly criticised by Professor Stephen Heppell of Anglia Polytechnic University, who has advised the Government on projects including the National College for School Leadership Online.

He said the Department for Education and Employment advice against personal addresses was “completely insane - it’s lazy, inappropriate and a complete cop-out”.

Research evidence clearly demonstrated that children needed their own online identity - and thus their own e-mail address - to build communities and make effective use of the Internet for learning, says Professor Heppell.

Niel McLean, of the British Educational Communications an Technology Agency, denied the advice was a knee-jerk reaction to campaigners such as Carol Vorderman about children being targeted on the Net.

A DFEE spokesperson said it was now inappropriate to give pupils personal e-mail addresses. However, many schools have already provided them and have not been told to revoke them. The DFEE said it was ensuring these schools had “effective security filters in place to prevent access to unsuitable material”.

The 46 pupils in the class taught by Jonathon Bishop, deputy head at Broadclyst primary, near Exeter, had their own address. Mr Bishop said a filtering system allowed e-mails to be monitored and pupils were taught about the dangers of passing on personal information to strangers. “We should be giving children the experience and opportunity to use e-mail in a safe way,” he said.