A group of small town teachers have a big idea called The Sleeve. It's a device that slips over the closer-arm of a door to prevent the door from being opened from the outside. The idea is to buy time for teachers and students during a school shooting.

Daniel Nietzel, President of Fighting Chance Solutions and middle-school teacher said he came up with the idea of The Sleeve after realizing the tactics they were taught during active-shooter drills weren't effective. He said the officer acting as the shooter was able to get into all the classrooms and "kill" everyone inside. The Sleeve is designed to be faster than tying a rope, cord, or belt around the closer-arm, which is what teachers are taught in his school district. "You're essentially tying the most important knot of your life," said Nietzel.

Nietzel's wife is also a teacher and he was worried about her not being able to secure all three of the doors in her classroom quickly enough to stop someone from entering. "It's in the back of the mind every time, every time we walk through those school doors, ya know, could this be the day," said Nietzel.

Tired of waiting for a better system, Nietzel and his team came up with a door-closer sleeve made of solid carbon steel that can withstand 550 foot-pounds of force.  Since its debut in early June, the device has gained national and international attention.  When there's an active shooter, seconds count, so The Sleeve is meant to be fast and easy. The device takes only a second to slip on.

The local Muscatine Community College bought The Sleeve for all of its classrooms. President of the college Bob Allbee said that although they don't ever expect a shooting to happen in their small town, he wants to be prepared.

"Hopefully we'll never use them, hopefully we'll just have to dust them every once in a while and they'll be on the wall," he explained. "But in case we need them, that's why they're there, again we're just trying to buy some time."

The Sleeve is painted 'Safety Red' much like fire alarms, or fire extinguishers. The idea is to help address concerns of teachers being locked out of their classrooms. Nietzel said the point of the color is to make sure students understand and associate the color with other safety devices. "When students think of this, see this, they think 'ok safety,' this is not to be messed with unless it's a life or death situation," said Nietzel. The Sleeve is small enough to be hidden in a drawer away from students, or can be displayed by the door.

The door closer-arms can vary so each sleeve is custom-made depending on measurements that must be taken before ordering. The Fighting Chance Solutions team is determined to keep production of The Sleeve in America and the devices are made in Muscatine, Iowa at Fabricators Plus.

Each Sleeve costs $65 and the company offers bulk order discounts. There are also $70 teacher gift certificates that include shipping. All the teacher has to send are measurements and they'll receive the Sleeve three to four weeks later.

Lauren Blanchard is a graduate of the Junior Reporter program at Fox News. She is now a multi-platform journalist and occasional general assignment news reporter. Follow her on Twitter: @LaurenBlanch12