By Tony Lopez

SACRAMENTO (CBS13) — While it can be frightening for some, it’s been a deadly mistake for others. Children are left behind on school buses, out of sight of drivers, locked in on sometimes sweltering days.

That’s why beginning next Friday, California school buses will have to be equipped with a special device to prevent a child from being left behind.

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Left in a school bus for nine hours in 90-degree heat, 19-year-old special needs student Paul Lee was found dead. His school bus driver did not check the bus before parking it in the yard in Whittier on Sept. 11, 2015.

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The California law named in Lee’s honor is designed to prevent future tragedies. It requires buttons to be installed in the back of every bus. After the driver pulls into the yard and shut off their bus, they are required to walk to the back of the bus and check for any remaining passengers.

The button must be pushed after turning off the bus to ensure the driver walks the length of the vehicle, the seats. The horn then honks when the driver disarms the system.

If a driver forgets to check the bus, its horn starts honking and school administrators will get an email.

The Elk Grove Unified School District installed this technology even before Governor Brown signed the bill in 2016. They have proof that the system works.

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“There has been an instance within the last year where they’ve walked the bus to press the button and there was a kid sleeping on the bus,” said Elk Grove Unified Director Transportation Matt Sanchez.

Paul Lee’s mother is so thankful California is taking action to keep kids safe.

“The signing of this bill is a warm hug from heaven,” she said. “I love you and I miss you. I’ll see you in heaven.”

Elk Grove Unified School District needs to make a few tweaks to its system so it is in compliance before the deadline next Friday. They plan to have the work done by Monday.

Swipe below to see strange laws on the books in California.

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