Biometric technology which allows them to be identified through their hands' unique vein patterns has been introduced at Todholm Primary in Paisley.
It means no more lost dinner money - and protects the identity of pupils who are entitled to free school meals.
The system identifies children with food allergies and encourages pupils to eat a balanced diet by providing a read-out of what they choose during the week.
Those behind the scheme now want to roll it out across Scotland and say it could be used to allow pupils to get in and out of school, register their attendance and take out library books.
However, critics said it is unnecessary and a possible breach of civil liberties.