KASSON, Minn. — Kasson-Mantorville Public Schools will hold a referendum in November, asking voters to approve an operating levy that would generate at least $500 per student per year for the next decade. The district’s school board approved the decision during a special meeting on Monday with a 5-2 vote. Board members Denise Heidt, Patrick Madery, Eric Mesa, Aaron Stockard and Mark Torkelson voted in favor of the amount. Board members Elizabeth…