The use of laptop computers by Australian schoolchildren is becoming a pain in the neck - for them, and for their teachers.

Researchers at Curtin University of Technology in Western Australia have warned that prolonged use of laptops could cause serious physical damage. They surveyed more than 300 students aged between 10 and 17 who used laptops for all their school work.

They found that students were spending more than three hours a day and up to 17 hours a week staring at the computer screen and carrying the machines, along with a load of books, with them to classes. The students reported discomfort in the neck, lower back, shoulders and head.

The researchers said the discomfort was due to the length of time and the unusual postures students adopted, as they often did not sit at a desk or table. In Victoria, teachers have been warned that laptops can cause neck and eye strain, tendonitis, muscle spasms, and back problems. The arrival of 11,000 laptops for teachers this year, with another 4,000 to come, has raised concerns that teachers will join the West Australian pupils in suffering as a result of inappropriate use of the computers.

The state education department has issued a guidance booklet to try to prevent injuries to teachers. The Australian Physiotherapy Association has also produced a booklet, Ten Tips for PC Use, aimed at parents and students.

Physiotherapists say that one of the main disadvantages is that the height of the laptop screen makes users bend their heads to see it.