Conducting a classroom waste audit is a hands-on way for kids to learn how to reduce their waste at school. Whether kindergarteners or highschoolers, waste audits resonate with students of all ages because everyone handles trash on a daily basis.

Good info and step by step process kids can use at school to reduce waste are here: http://blog.trashbackwards.com/2012/11/05/10-simple-steps-to-conducting-a-classroom-waste-audit/