Dexter Chaney, a 29-year-old Chicago area teacher, had no idea what was about to happen when he and his students attended an assembly at Ryerson Elementary on Monday.

Rich Hein / Chicago Sun-Times via AP

Third-grade teacher Dexter Chaney from Martin A. Ryerson Elementary School in Chicago reacts after being named recipient of the Milken National Educator Award, a prestigious national teaching award. Chaney was one of 55 nationwide to receive the honor, and the only one from Illinois.

Rich Hein / Chicago Sun-Times via AP

Dexter Chaney is congratulated by his students.

The Chicago Tribune reports that Chaney learned he'd won the Milken Educator Award during the school gathering. The school’s principal describes Chaney as a role model to every child in the school. The award carries a $25,000 prize.

Watch NBCChicago.com's coverage of the assembly.