Schoolchildren in Boulder County are giving a thumbs-down to healthier food in the cafeteria. The Boulder Valley School District says fewer elementary school students are eating hot lunches after the district spent hundreds of thousands to give their cafeterias a healthy makeover. Hot lunches now avoid processed food in favor of fresh fruits and whole grains. Hot lunch sales are up among middle- and high-school students. But among the elementary school set, who make up the largest percentage of hot lunch customers, hot lunch sales are down. School officials told the Daily Camera newspaper that they're interviewing young diners and inviting parents to have lunch at school next month in an effort to boost sales.