Some children ask their teachers when they arrive at school what's going to be served, she said from a Toronto school.
"They're waiting for that snack that morning, maybe their only breakfast that they get," Wynne said.
"And so it's a really important program because we know that kids can't focus if they're hungry."
Wynne was at the school to bring attention to Monday's announcement that her government plans to expand the program to 340 new elementary and high schools, as well as on-reserve First Nations schools beginning in northern Ontario.
The $32-million funding is part of a five-year plan to enhance the program.