While school meals are often the healthiest option for students, lunch participation remains relatively low. Few approaches for increasing participation have leveraged teachers' potential social influence. We determined if a teacher intervention about the benefits of school lunch could improve teachers' perceptions of, and participation in, school lunch, and encouragement of students to eat school lunch. This repeated cross-sectional study included teacher/student survey administration in spring of 2016 and 2018 in 19 public secondary schools (9 intervention, 10 comparison) educating students of ages ≈ 11-18. Intervention teachers received monthly newsletters; lunch taste tests; and a promotional video and website. Mixed effects models with a random effect for school showed the proportion of teachers that reported eating with students increased in intervention schools relative to control schools (difference-in-change: 7.6%; 95% CI: 3.578%, 14.861%), as did student agreement that adults at their schools encouraged them to eat school lunch (difference-in-change: 0.15 on a 5-point scale; 95% CI: 0.061, 0.244). There were no between-group differences in teachers' perceptions of school meals or teachers' lunch participation. These findings suggest that teachers' perceptions of school meals do not necessarily need to improve to promote the school lunch program to students. However, to see meaningful change in teacher lunch participation, the taste of school meals likely needs improving.
Keywords: school lunch; school lunch participation; school lunch perceptions; secondary schools; teacher intervention.