ADDISON, Ill. (CBS) — The tragedy in Connecticut has many schools re-evaluating their security procedures. But one school campus in Addison already did that a couple of months ago.

On Oct. 5, Indian Trail Junior High was locked down for three hours after authorities thought an intruder restrained a female student in a restroom and was still in the building.

It turned out to be a false alarm. But as CBS 2’s Chris Martinez reports, the lessons learned are very real.

It’s not what could happen at the school, but rather what did that led to change.

Enhanced locks at one doorway, a new sign-in desk at another are part of security upgrades after a real lock-down occurred earlier this year. It was later determined a female student lied about the intruder.

“A student unfortunately made a poor choice, but it’s also a learning experience for us all,” Principal Craig Bennett says.

Police rushed in, and parents said they were left without answers for hours.

It all went down like the real deal, revealing ways the school might do better.

One example: getting everyone involved in drills.

“Now, we practice the same exact routine, including our maintenance staff, our food service staff,” Addison Elementary School District 4 Supt. John Langton says.

The massacre Friday morning, nearly 900 miles away, reminds officials why.

“Now they know why we do our drills,” Bennett said.

The school has already held a lockdown drill since October, and just as they did with their own response they’ll also study the response in Connecticut to see what they might learn from that tragedy.

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