Teacher's Genius Bread Experiment Shows Why Hand-Washing Matters

by Julie Scagell
Originally Published: 
Courtesy of Jaralee Annice Metcalf

The teacher used bread to show just how easily we can spread germs

One of the most important lessons we teach our kids is the importance of washing their hands. In fact, when we’re out and my kids get up to go to the bathroom, they’re like “Yes, we know mom. Wash our hands.” One teacher decided to conduct an experiment to show her students just how important it is, especially during cold and flu season.

“We did a science project in class this last month as flu season was starting,” teacher Dayna Robertson and behavioral specialist Jaralee Metcalf posted on Facebook. “We took fresh bread and touched it. We did one slice untouched. One with unwashed hands. One with hand sanitizer. One with washed hands with warm water and soap. Then we decided to rub a piece on all our classroom Chromebooks,” they wrote. They put each piece of bread in a sealed Ziploc bag and waited. The results are eye-opening — and super gross.

As you can see, the bread that had been touched by dirty hands and wiped on the students’ Chromebooks had the most mold, and the one with hand sanitizer is a close third. “As somebody who is sick and tired of being sick and tired of being sick and tired,” the Idaho teachers wrote, “Wash your hands! Remind your kids to wash their hands! And hand sanitizer is not an alternative to washing hands!! At all!”

It’s not the first time this experiment has been done, but Robertson took it one step further showing that hand sanitizer, while better than nothing, doesn’t do the job of good old soap and water. Having a visual representation, especially for elementary-aged kids, goes a long way in explaining why we all harp on the importance of having clean hands.

Facebook/Jaralee Metcalf

Robertson tells Scary Mommy that this is only her second year teaching, and the first time doing this experiment. “We had just finished a science lesson on how leaves break down during winter. The kids were kind of grossed out by the mold, so we decided to run our own version using germs and mold from our own environment,” she said. After posting the results, they received a lot of support but also, a lot of people criticized the experiment saying results were fake because bread molds on its own anyway, and that it wasn’t fair to use a fresh piece for the picture. Some folks even suggested that they were only out to give Chromebooks a bad name. Robertson also mentioned in the post they do sanitize the Chromebooks but didn’t that day for the purposes of this experiment.

Facebook/Jaralee Metcalf

What’s more, “Lots of people actually DEFENDED not washing their hands!” Robertson says. “That was shocking! It really was just a simple classroom experiment to teach about mold but we have all learned more about how easily we can spread the germs we can’t see.”

If this isn’t enough to get everyone to wash their hands moving forward, we don’t know what is.

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