I have heard a lot of schools bragging about being zero-waste. But if you ask them...how did they come to a figure zero...they have no answers. After all in an equation, one needs to prove how everything = 0.
The truth is that most of the schools brag about their waste management systems of composting and waste segregation without having an idea about the exact amount of waste which is generated in the school.
Finding the exact amount of waste generated on a daily basis is actually called a waste audit.
There's a small film I have made on doing a waste audit. Do watch it on youtube at the following link. This is the first ever video documentation of a waste audit in India and perhaps South Asia.
Apart from it being an enviornmental activity...it has immense educational value of teaching scientific data collection as also social sensitivity towards fellow human beings, who help us keep our cities clean.