The Times reported last week that parents at an independent school in north London had protested when fingerprints were allegedly taken from pupils without consent with a view to the fingerprints being used for the automated lunch payment system. One of those pupils subsequently wrote to the Times saying he wasn't bothered: "Most of the pupils were excited about this new system, and any who were unconvinced were allowed to decline having their fingerprints taken. It was no inconvenience to anybody, and we were in fact pleased that we were allowed to miss half of our maths lesson." (For those without access to the Times online, the story was also covered by Mail Online here.)
The use of fingerprints and other biometric data does of course engage a person's Article 8 rights. Being "personal data", it is also subject to the provisions of the Data Protection Act 1998. A useful review of the legal issues is here.
So far as the use of biometric data in schools is concerned, this will be subject to additional statutory control from 1 September 2013 pursuant to the Protection of Freedoms Act 2012. See the recently issued guidance from the Department for Education here, which explains the need for prior parental consent.