['To determine the reliability and validity of a questionnaire measuring fruit and vegetable (FV) self-efficacy and social norms during school lunch among 5th graders.', 'In this cross-sectional study, students completed lunch food records and a psychosocial questionnaire measuring school lunch FV self-efficacy and social norms regarding consumption during the fall and spring semesters. Test-retest reliability was assessed between fall and spring semesters. The measurement model was cross-validated in the spring data.', 'One middle school in Houston, Texas.', '275 fifth graders in the 1998 fall semester and 262 of these fifth graders in the 1999 spring semester.', 'FV consumption and psychosocial variables.', 'Principal components analyses, confirmatory factor analyses and bivariate correlations.', 'Three scales were identified: Fruit Self-Efficacy, Vegetable Self-Efficacy, and FV Social Norms. FV self-efficacy were positively correlated with low-fat vegetable and fruit consumption. Social norms were positively correlated with total vegetable, low-fat vegetable, fruit and total FV consumption.'] Are self-efficacy and norm measures for lunch fruit and vegetable consumption reliable and valid among fifth grade students?