The California Agricultural Teachers’ Association applauded Tomales High School’s agricultural department—a popular program that attracts nearly a third of the school’s student body—presenting the department’s leader with an award earlier this summer at a ceremony in San Luis Obispo. Bill Costanzo, the department’s head and sole teacher, oversees seven courses at Tomales—a school he said mostly serves children from ranching, dairying and oyster farming families. “This is huge for me. I’ve been working hard at…