Plastic and garbage in general have been long serious problem for humans and environment. People’s awareness in managing plastic garbage is still low and the students at school in term of their awareness toward green world development is also not different. A special technique to educate students to have better way in managing plastic garbage has been made and implemented at a junior high school, SMP N 1 Banjarnegara in Central Java, Indonesia. Using 3 M memilah (selecting), mencuci (washing), and menjual (selling) plastic garbage, students can prevent the plastic garbage go into nature so that they can minimize the degradation of environment in order to build the green world. 3M is found to be effective to make the school always clean and neat and the students become aware of the importance of protecting the nature from plastic garbage.<br />