Kids lose their school IDs but they don't often lose their eyeballs.

That's one of the reasons why a growing number of schools are replacing traditional identification cards with iris scanners. By the fall, several schools -- ranging from elementary schools to colleges -- will be rolling out various iris scanning security methods.

Winthrop University in South Carolina is testing out iris scanning technology during freshman orientation this summer. Students had their eyes scanned as they received their ID cards in June.

"Iris scanning has a very high level of accuracy, and you don't have to touch anything, said James Hammond, head of Winthrop University's Information Technology department. "It can be hands free security."

The college will be deploying scanning technology from New Jersey-based security company Iris ID.

Related story: Hackers' next target: Your eyeballs

South Dakota-based Blinkspot manufactures iris scanners specifically for use on school buses. When elementary school students come aboard, they look into a scanner (it looks like a pair of binoculars). The reader will beep if they're on the right bus and honk if they're on the wrong one.

The Blinkspot scanner syncs with a mobile app that parents can use to see where their child is. Every time a child boards or exits the bus, his parent gets an email or text with the child's photograph, a Google map where they boarded or exited the bus, as well as the time and date.

Iris-scanning is part of a growing trend called "biometrics," a type of security that recognizes physical characteristics to identify people. As the technology becomes faster and cheaper to build, several security equipment manufacturers are looking at biometric methods like iris scanning as the ID badge of the future.

In the next year, industry insiders say the technology will be available all over-- from banks to airports. That means instead of entering your pin number, you can gain access to an ATM in a blink. Used in an airport, the system will analyze your iris as you pass through security, identifying and welcoming you by name.

One company developing that technology is Eyelock. The company's scanners are already in use in foreign airports and at high-security offices, including Bank of America's (BAC) North Carolina headquarters.

Eyelock's technology records video of your eyeball and uses an algorithm to find the best image of each eye. Eyelock is also entering the school market, piloting their devices in elementary school districts and nursery schools around the country.

"Imagine a world where you're no longer reliant on user names and passwords," Eyelock CMO Anthony Antolino told CNNMoney. "If we're going through a turnstile and you have authorization to go beyond that, it'll open the turnstile for you, if you embed it into a tablet or PC, it will unlock your phone or your tablet or it will log you into your email account."

Eyelock's airport security technology can process up to fifty people per minute.

"You walk through without stopping, you look at the camera, it recognizes you in less than one second," Antolino said. "In the case of customs, by the time you approach the customs agent your profile would pull up and present your documents for authorization."

Though some privacy advocates worry that convenience could be coming at the expense of security.

The iris scanning companies note that the data their scanners collect is encrypted -- an outsider would only see 1s and 0s if they went in search of your iris scans. And the companies themselves don't collect any of the data -- the schools, airports and businesses that use them own the data.

"It's sort of like a brave new world; the new technology is sort of scary," said Page Bowden, a parent of a student at Winthrop University's on-campus nursery school. "But when you stop to actually think about it, and think about the level of security that [it] affords you as a parent and your children, it's worth it."