Starting in January, Patrick Henry High School students will use their thumbs for more than just handling food during lunch.

The Roanoke high school has installed a biometric thumbprint reader in its new cafeteria, which will go into use starting Jan. 2, when students return from winter break.

The reader will replace the current system, in which students punch in a six-digit identification number to pay for their lunch. It's intended to eliminate mistakes that sometimes occur when students tap in their numbers, said Patrick Henry Principal Gary Leah.

"We've got 1,800 students going through the line and there are mistakes that can be made," Leah said.

The new system relies on a student's thumb or forefinger, although it doesn't actually record the print.

Instead, it identifies five unique characteristics in the print and assigns a numerical value, said Bernard Godek, associate superintendent for management in Roanoke schools.

"It speeds up the process of people going through lunch lines," Godek said. "It's a faultless ID system where someone can't accidentally or intentionally put in the wrong student number."

The numbers link to accounts which not only include the amount of money a student has paid for lunch, but also indicate if that student qualifies for free or reduced lunch prices.

Letters informing parents of the change were to be sent out Friday. It is not clear whether bad weather and subsequent cancellation of school may have affected that.

Trisha Edwards, president of the Parent-Teacher-Student Association at Patrick Henry, said she hasn't yet heard any reaction from parents. She said she doesn't expect any until the school's letters are received.

However, one parent is already upset.

Eileen Anderson said her daughters, in the ninth and 11th grades, told her about the planned change after hearing from Leah in class this week. She considers the biometric system a violation of students' personal rights.

"As a parent I feel reluctant to give away that bit of privacy for my children," Anderson said. "They're very young and it should be their decision as an adult whether they want their fingerprints taken. It concerns me the schools have gotten so impersonal they can't remember who is who."

Godek, however, said the system won't record the actual thumbprints, but rather a numerical value based on them.

"It takes five key elements off of a print and assigns it a numerical value," Godek said. "That's what's kept inside a database ... It doesn't store any fingerprints at all."

To use an analogy, the system doesn't record the fingerprint, but some information about it. It's like having a description of a person (height, weight, etc.) instead of a photograph.

Similar systems have been used in other school systems around the country, where they've generated debate about privacy and potential for misuse.

Godek said a biometric system was tested in Prince William County last year. Although some parents initially expressed concern about the technology, he said, they warmed to it after the school released more information.

Staff writers Shawna Morrison and Andrew Kantor and news researcher Belinda Harris contributed to this report.