Why is this being done at a public school?

ABC News is reporting that Eye Scan Technology is Coming to Schools

Parents who want to pick up their kids at school in one New Jersey district now can submit to iris scans, as the technology that helps keep our nation's airports and hotels safe begins to make its way further into American lives.

As many as four adults can be designated to pick up each child in the district, but in order to be authorized to come into school, they will be asked to register with the district's iris recognition security and visitor management system. At this point, the New Jersey program is not mandatory.

When picking up a child, the adult provides a driver's license and then submits to an eye scan. If the iris image camera recognizes his or her eyes, the door clicks open. If someone tries to slip in behind an authorized person, the system triggers a siren and red flashing lights in the front office. The entire process takes just seconds.

I know that child abduction is a serious concerns of parents and schools today, but this seems a little over the top, and presumably very expensive. In case you were wondering who is sponsoring this trial:

The Freehold Borough School District launched this high-tech, high-wattage security system on Monday with funding from the Department of Justice as part of a study on the system's effectiveness.

Why in the world would the DOJ be interested in installing this type of system into a school system? Also does the government (this is after all a public school) have the right to force a parent to submit a biological scan in order to pick up their child? This also opens up a Pandora's box of questions regarding the management of this type of systems; where are these iris scans being stored; how long will they be stored; who has access to them while they are being stored, etc.

This has a sneaky feeling of Big Brother sneaking into our lives. Is this another case of Bush's domestic spying, and the building of a data warehouse to track individual attributes and movements, without the public even realizing this is happening or just a school trying to protect its students? Too many questions, which hopefully those in Freehold NJ are asking before implementing this system.