The present study aimed to verify the instrument's reliability and validity for assessing children and adolescents' risk perception, knowledge, and food safety practices in the school context. Moreover, it aimed to test the hypothesis that both application methods (paper and pencil (PAPI) and online) are valid. The instrument comprised three questionnaires and followed a strict protocol to combine online and PAPI models, resulting in five application forms. The sample consisted of 439 Brazilian students from 10 to 14 years old (y/o). The results related to reliability and validity indicated that the knowledge questionnaire presented adequate stability and discriminant validity coefficients. The self-reported practices questionnaire obtained acceptable coefficients of stability and internal consistency. Regarding risk perception data, it was observed that students attribute a low probability of Foodborne Diseases (FBD) outbreaks occurrence and low severity of possible symptoms. In addition, students demonstrated insufficient knowledge and inadequate practices on issues related to failures associated with the time and temperature of preparation, storage, and exposure of food, contamination of food, and consumption of unsafe food. In this context, the reproducibility and validity indices need to be interpreted and discussed correctly, and young people in food safety actions are a priority in facing FBD.