Carrie Underwoodsurprised students at Andrew Jackson Elementary School during choir rehearsal in advance of their performance at the Country Music Awards Music Festival back in June.

A clip uploaded to YouTube on Monday shows the 36-year-old singer popping in on a rehearsal, and the reactions from the students are priceless.

“You guys are going to be so amazing,” Underwood praised the young singers during her surprise visit. “That crowd is not going to know what hit ’em.”

The foundation has invested nearly $12 million into Nashville public schools since 2006, providing instruments and equipment to the 87,000 students within the district, according to theirwebsite.

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source: people.com