A middle school in Lawrence, Kansas gave their students an impromptu class on kindness, helping them to shower gratitude on a group of construction workers building an addition onto the school.

The principal at Corpus Christ Catholic School had the idea of serving lunch to the guys in hard hats, but the teachers took the idea a step further.

"The picketing idea was cooked up at a faculty meeting," said Jill Hilton LaPoint, who posted this photo on Facebook. "Our art teacher made the signs for kids to carry back and forth as they went to lunch or PE. It was a happy afternoon here!"

The kids served them lunch from Bigg's BBQ.

"It was much appreciated," added LaPoint. "I heard that some of the guys even got a little teary."

(CORRECTION: The original story had the incorrect school name and location.)