The PS22 chorus hadn’t even begun singing before teacher Adriana Lopez began to tear up. Their version of Martina McBride’s “I’m Gonna Love You Through It” was aimed at her. Lopez was recently diagnosed with breast cancer, and the choral director explains the group was "inspired by your fighting spirit" and wanted to give back.

The Staten Island, N.Y., chorus is famous for cover songs and for performing with superstars like Carrie Underwood. Here they tackle McBride’s 2011 hit that was used as an anthem for Breast Cancer Awareness Month. Lopez sits in the bleachers, dabbing her eyes with a tissue as the kids work through the song. After they finish, she offers thanks and talks about the situation.

“It’s not easy,” she says, “but I will get through it because I have wonderful friends at school.”

It’s not the first time PS22 has paid tribute during one of their covers. In December 2012 they dedicated a performance to the families affected by the Sandy Hook Elementary School shootings. They sang the Newton, Conn., elementary school’s song.

Katy Perry, Phillip Phillips and Jennifer Hudson are other stars the PS22 chorus has performed with. They've appeared on Oprah twice and played for the President, Lady Gaga and many more. To date they have more than 100,000 subscribers and 69 million views at their YouTube channel. The group of fifth graders are ordinary students, not those from a magnet school or school for the arts.

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