A second secondary school has adopted controversial facial recognition technology to register pupils.
City of Ely Community College has joined St Neots, another Cambridgeshire school, in trialling the Face Register system that can sign in pupils in just 1.5 seconds.
The technology, which will be launched nationally in April, has been developed by Aurora Computer Systems. It works by matching the infra-red scan of pupils' faces with key facial features stored on a central system. Each pupil has a pin code, which can help the system distinguish identical twins.
Richard Baker, City of Ely's principal, said the system liberated teachers' time, improved evacuation procedures and had proven a hit with pupils. "They love the idea of taking responsibility for their own registration and using Mission: Impossible-style systems," he said.
But critics feel the system is too expensive. And they are concerned about the potential applications of such technology.
Liberal Democrat Councillor Andrew Makinson successfully campaigned against using it in Liverpool schools, citing both the cost and the depersonalisation involved.
"Though it's a tremendous waste of money, devised by IT junkies who don't understand the consequences - the fact that children are now growing up in a surveillance state is a far greater worry," he said.
Phil Booth, national co-ordinator for the human rights organisation NO2ID, is concerned that by using this technology, schools are neglecting other important features.
"Putting in systems like these sends out the message that the school is a secure environment - something they should be promoting through their ethos and culture," he said.
Mr Booth said that, in other schools, pupils had been threatened with exclusion if they refused to register their fingerprints.
"It is unbelievable that parents and children are not given a choice," he said. "Clearly, it demonstrates that students must value their personal information, know where it is being used and who is gaining access to it."
Mr Booth, a former teacher, said that pupils would ultimately suffer if the technology were introduced nationally. "It is very important that, at the beginning of each day, students have some form of interaction with a human being," he said. "To systematically remove human contact from schools is making them a more inhuman place."