RFID tags for students in the US

by Bill Glover

Related link: http://www.billglover.com/blog/archives/000107.html

SUTTER, Calif. -- The only grade school in this rural town is requiring students to wear radio frequency identification badges that can track their every move. Some parents are outraged, fearing it will take away their children's privacy.
The badges introduced at Brittan Elementary School on Jan. 18 rely on the same radio frequency and scanner technology that companies use to track livestock and product inventory. Similar devices have recently been used to monitor youngsters in some parts of Japan.

How is this better/worse than a student ID card?