First-grade students in Grand Marais, MN are doing their part to fight the COVID-19 virus with something they call "virus traps."

A photo shared to Twitter reveals a project that grade-schoolers in Northern Minnesota have been working on. In an online interaction with Jim Rosenthal, CEO of Tex-Air Filters, Minnesota mom Anne Brataas showed off the CR Box that local students had built.

"In remote northern Minnesota 1st graders are building CR boxes, renaming them Virus Traps," she said on Twitter. She goes on to say that students are fundraising to make 20 more for distribution.

Nicknamed a "virus trap" by the students, the CR Box is actually known as a Corsi-Rosenthal Box -- named after its two creators Richard Corsi and Jim Rosenthal. At the onset of COVID-19, Corsi had the idea for a DIY air purification unit and brought it to Rosenthal who helped build it with his company's air filters. Essentially, the box or cube consists of air filters on four sides to collect particles with a box fan on top to suck in air and then blow filtered air out.

The "virus trap" was built by members of Story Scouts -- a joint program between Minnesota Children's Press and Cook County YMCA -- in Grand Marais. Story Scout's motto is "No Child Left Indoors with Coronavirus!" A 12-picture guide to building a CR Box is available at the Story scouts website.

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