Scientists have said there is no evidence to suggest a link between the use of wi-fi and damage to health.
BBC programme Panorama found that radiation levels from wi-fi in one school was up to three times the level of mobile phone mast radiation.
The readings were 600 times below the government's safety limits but there is ongoing debate about wi-fi use.
Sir William Stewart, chairman of the Health Protection Agency, has said there needs to be a review of wi-fi.
He told Panorama that there was evidence that low-level radiation - from devices like mobile phones and wi-fi - did cause adverse health effects.
But some experts in the scientific community have disagreed with his assessment.
"Wi-fi seems unlikely to pose any risk to health," said Professor Lawrie Challis, of Nottingham University.
Prof Challis, chairman of the Mobile Telecommunications and Health Research (MTHR) programme management committee, said: "Wi-fi exposures are usually very small - the transmitters are low power and some distance from the body.
"They can be near to the body, however, when a laptop is on one's lap and my own view is that just as we encourage young children not to use mobile phones we should also encourage them to use their laptops on a table rather than their lap, if they are going online for a long time."
As part of its investigation, Panorama visited a school in Norwich, with more than 1,000 pupils, to compare the level of radiation from a typical mobile phone mast with that of wi-fi in the classroom.
Readings taken for the programme, broadcast on BBC One on Monday, showed the height of
wi-fi signal strength to be three times higher in the school classroom than the main beam of radiation intensity from a mobile phone mast.
Source - BBC