A study by Futurelab, an education technology research body, shows hand-held devices are invaluable for learning, as long as they connect remotely to the internet and are backed up by computers.

But schools are investing in the hand-held devices as cheaper alternatives to computers in order to meet government expectations that every learner has appropriate access to technology both in and after school.

Many of the personal diary organisers and MP3 players do not connect remotely to the internet, because that would require schools to approve the use of contentious cellphone or WiFi microwave technology. Though there is no compelling scientific evidence that microwave pulses are harmful to children, most schools have accepted the Department for Education and Skills advice that they take a cautious approach.

Becta, the official education technology agency, estimates that schools spent pound;6.5million on personal diary assistants (PDAs), Smartphones, iPods and other MP3 players for pupils in 2005.

Only one in 40 primary schools, and one in 100 secondary schools had invested in the technology in 2005 - but a third were working towards providing mobile devices for all pupils. The Futurelab report, which studied the use of hand-held devices in 26 schools over two years, found that their effective use helped boost children’s enthusiam for the subjects they were learning.

Staff at Dudley, one of the local authorities studied, reported an increase in overall attendance and a decrease in poor behaviour after they supplied WiFi-connected PDAs to 300 pupils. But in Shropshire, Stiperstones school ended its trial of Dell Axim PDAs, which did not connect to computers or the internet, because adequate programs were unavailable and they were “inferior” to computers.

lwww.futurelab.org.ukresearchhandbooks.htm