If the food is kept warm for too long, it will lead to the loss of nutrients and can not meet the energy needs of students during their growth period. When the temperature is high in summer, food that has been kept warm for a long time may go bad. The primary and secondary school stage is a critical period for children's physical and mental growth. Adequate sleep and correct sleeping posture are necessary factors to ensure the healthy growth of students. Due to the lack of lunch break conditions in most schools, students can only sleep on their desks after lunch, which can not guarantee the quality of students' sleep, and may even lead to abnormal development of students for a long time.