Just as the U.S. Department of Agriculture mandates Radio Frequency Identification Device chips to monitor livestock, a Texas school district just begun implanting the devices on student identification cards to monitor pupils' movements on campus, and to track them as they come and go from school.

Tagging school children with RFID chips is uncommon, but not new. A federally funded preschool in Richmond, California, began embedding RFID chips in students' clothing in 2010. And an elementary school outside of Sacramento, California, scrubbed a plan in 2005 amid a parental uproar. And a Houston, Texas, school district began using the chips to monitor students on 13 campuses in 2004.

It was only a matter of time. Radio frequency identification devices are a daily part of the electronic age, and are fast becoming a part of passports, libraries and payment cards, and are widely expected to replace bar-code labels on consumer goods.

And it appears that the educational move to Big Brother-style monitoring is motivated mainly by money, despite privacy and health concerns.

Two schools at the Northside Independent School District in San Antonio began issuing the RFID-chip-laden student-body cards when classes began last Monday. Like most state-financed schools, their budgets are tied to average daily attendance. If a student is not in his seat during morning roll call, the district doesn't receive daily funding for that pupil, because the school has no way of knowing for sure if the student is there.

But with the RFID tracking, students not at their desk but tracked on campus are counted as being in school that day, and the district receives its daily allotment for that student.

"What we have found, they are there, they're in the building and not in their chairs. They are in the cafeteria, with counselors, in stairwells or a variety of places, some legitimately and some not," district spokesman Pascual Gonzalez said in a telephone interview. "If they are on campus, we can legally count them present."

The Spring Independent School District in Houston echoed the same theory when it announced results of its program in 2010. "RFID readers situated throughout each campus are used to identify where students are located in the building, which can be used to verify the student's attendance for ADA funding and course credit purposes," the district said.

But privacy groups are wary.

"We don't think kids in schools should be treated like cattle," Marc Rotenberg, the executive director of the Electronic Privacy Information Center, said in a telephone interview. "We generally don't like it. My take on RFID is it's fine for products, but not so much for people. That's one of the places where the lines need to be drawn. "

But there appears to be dozens of companies who see no need to draw such a line and offer their RFID wares to monitor students in what is still a tiny but growing market. Among the biggest companies in the market: AT&T.

"One day soon, home room teachers in your local middle and high schools may stop scanning rows of desks and making each student yell out 'Here!' during a morning roll call. Instead, small cards, or tags, carried by each student will transmit a unique serial number via radio signal to an electronic reader near the school door," AT&T says in its RFID-student advertising materials.

Gonzalez said there has been minimal parental and student opposition to the program at John Jay High School and Anson Jones Middle School. The pilot project could expand to the Northside Independent School District's 110 other schools, he said.As for privacy, the system only monitors a student's movements on campus. Once a student leaves campus, the chips no longer communicate with the district's sensors.He said the chips, which are not encrypted and chronicle students only by a serial number, also assist school officials to pinpoint where kids are at any given time, which he says is good for safety reasons. "With this RFID, we know exactly where the kid is within the school," he said noting students are required to wear the ID on a lanyard at all times on campus.

The lack of encryption makes it not technically difficult to clone a card to impersonate a fellow student or to create a substitute card to play hooky, and makes the cards readable by anyone who wanted to install their own RFID reader, though all they would get is a serial number that's correlated with the student's ID number in a school database.

EPIC's Rotenberg was among about two dozen health and privacy advocates who signed an August position paper blasting the use of RFID chips in schools.

The paper, which included signatures from the American Civil Liberties Union, Electronic Frontier Foundation and, among others, Big Brother Watch, said the RFID systems may have "potential" (.pdf) health risks, too.

"RFID systems emit electromagnetic radiation, and there are lingering questions about whether human health might be affected in environments where the reading devices are pervasive," the paper said. "This concern and the dehumanizing effects of ubiquitous surveillance may place additional stress on students, parents, and teachers."

Gonzalez said John Jay High has 200 surveillance cameras and Anson Jones Middle School, about 90.

"The kids," he said, "are used to being monitored."