There must be appropriate punishment to deal with wasteful students, punishment is not the purpose, let him know that the food is not easy to come, although the education of the children do not waste is not in the scope of the examination, but this is the most important in the teaching and educating people. I remember when I was a student, the school would show us movies about the shameful waste, because I was a child of the countryside, never went to the cinema at all, so that time especially like to watch movies, and each movie will really bring a great impact to the students. It's like watching movies about chivalry to be a chivalrous person, and watching movies about wastefulness being shameful and conservation being honorable can be watched and learned from, I remember watching a documentary about rice.
Then there is the teaching by example, parents and teachers work together to let children know that wasting food is a bad thing, children are more reversible, more receptive to new things than adults, so what you give him, what he has in mind. And I've always disagreed with the idea of teachers having a teacher's cafeteria and students having a student's cafeteria, it just seems strange to eat a meal, why is this! If the students do not waste, then the teacher has to sit in the pile of students, the party to teach to change them, otherwise the meal time, the teacher is not in the cafeteria students also think the teacher's rice than his incense it! The more you look at your own rice, the more you think the teacher's rice must be fragrant.Parents educate their children, do not just not let the child waste, and forget what the child really want to eat, everyone's tastes are different, parents can not just do what they like to eat dishes, and then forced the child to also eat clean, this is not right. Although the nutrition should be balanced, but if the child always eat can not eat what you want to eat, then it will be more and more resistant, what do you care what is wasted or not wasted, the parents do not waste, because to do things you like to eat, why the child has to follow your taste.
Then again to the punishment system, which is essential to the school of an education, no matter who did not do a good thing, should be punished, otherwise the child grows up unscrupulous, and then want to educate it is too late. So when the child wasted meals, give some tolerance within the punishment is possible, this teacher and parents to communicate well, some parents will not be educated, you want to punish his child, he still have to mess with you.