Check the school policy on cashless catering:http://www.netherhall.org/information/cashless-catering/
Netherhall will be launching a new cashless catering system in to the food hall from Monday 5th July 2010. This system allows each pupil to have an individual cash balance and record what the balance is spent on at any time or day.
The system uses biometrics to identify each pupil. This means that to pay for food their fingerprint is scanned at the point of sale. The image of their fingerprint is turned in to a number, so the image of their print is not stored. The total cost of their food is deducted from their balance.
Dinner money is now paid online through the WisePay system, below, using a credit or debit card. Parents / carers will receive a username and password as well as instructions on how to ‘top up’ your child’s account.
Each pupil will has a daily spend limit of £4.00. This means they cannot spend an entire weekly balance in one day. Specific limits can be set by contacting the Catering Manager in writing.
Please note, it is your responsibility to ensure your child has enough credit to buy their school dinner. Payments are made in advance, weekly, monthly or termly and take 12 hours to apply before the balance is available to spend in school. No cash will be accepted after Monday 5th July 2010.
The system works in the same way for those pupils entitled to free school meals – balanced will be topped up by the system daily for lunch time meals. You will be able to add additional credit on top of this allowance for break time snacks should you wish.
Only mentions fingerprints (as I suspected). No mention of iris or DNA.
There are a couple of PDF documents at the link above. One has an FAQ which states:
What happens when my child leaves the School?
When a student leaves school all data can be deleted very easily.
Note the use of can rather than will!
Can't find any policies discussing other biometrics.