The objective of this study was to investigate the effect of occasional mid-morning snacks (MMS) on dietary behaviors and school life among elementary students. The students, mothers, and teachers from two elementary schools in Seoul were selected. The schools have been provided a steamed sweet-potato or potato, or a piece of rice-cake or cake with a pack of milk as MMS 3-4 times a month for more than 3 years. Most students were satisfied with the MMS. Mothers and teachers reported that their children or students were happier, more active, and more energetic in school with MMS. Furthermore, the students answered that they could drink milk better on the day when the school provided MMS. Many students felt that it was relevant to serve a simple menu at lunch time if they were served MMS. Also, students became more interested in school meals or foods with MMS. In addition, mothers who had jobs wanted more frequent MMS. The degree of satisfaction about MMS of the teachers was higher than that of students or mothers. Many teachers thought that their students drank milk better with MMS and further, that it made students to drink more milk on other days. In conclusion, MMS had positive effects on the dietary behavior and school life of elementary students. Therefore, it can be a good option for eliminating skipping breakfast because it provides more nutrition, makes students drink more milk, and allows students to enjoy school activities more.