The Mathematics of Trash

Originally appears in the Summer 2010 issue

Across the industrialized world, the amount of solid waste sent to landfills each year is hard to fathom. Did you know that the United States cranks out about 250 million tons (approximately 225 million metric tons) of residential and commercial waste per year[1]? That’s approximately 500 million cubic yards. In Canada, 30 million tons per year are generated[2], while Australians generate approximately 35 million tons[3].  While students understand that these are big numbers, it can be hard for them — and many adults — to really grasp the magnitude of these volumes. After all, when was the last time you saw 250 million tons of anything in one place?

The following lesson uses mathematics to help students grasp the waste problem on a more familiar and meaningful level. These activities are appropriate for 3^rd through 5^th grade students studying graphing and multiplication, but they can easily be adjusted up or down.