Of all the ways schools and parents are encouraging kids to wash their hands, one teacher's simple hack stands out as pure genius.

"We always experience a spike in illness and absentees this time of year due to different viruses and the common cold," said Shauna Woods, a third grade teacher at Hallsville Schools in Hallsville, Missouri. "It's a fact of life that many kids are in close corners, interacting with one another all day. They share many things, including germs."

Woods has been teaching for eight years and was trying to think of a way to promote hygiene in the classroom to minimize sickness, she told "Good Morning America." Even though her students have access to a sink, hand sanitizer and disinfectant wipes at all times, she wanted to entice the kids to wash their hands more.

So she stamped them.

"I've had a 'Mrs. Woods' stamp for years and have used it to stamp my classroom books," Woods said. "I decided to grab that on a Monday morning, told students to wash their hands in the classroom sink and then come see their teacher -- this was their morning work as we call it. I put the stamp on their hands and they were sold when I told them prizes were involved."

That first day was "training day." Because the kids knew they would get a prize once the stamp was gone, they wanted it off right away.

But "once we went over the expectations and purpose, it became a routine for all of my students," she said. "Each morning since then, they get their stamp and go about their day. I check for their stamp at the end of the day and if it's faded or gone, they get their prize."

The teacher called it a "great motivator" for the kids. The goal, she said, is to get the kids to a place where washing their hands multiple times a day is second nature.

"Let's be honest, some student's biggest worry is if they'll get to recess on time," Woods said. "Providing a visual reminder and incentive has boosted their hygiene regiment. I even joined in on the fun and put a stamp on my hand to be their positive role model."