Student Worksheet

Thought-starter: What are the 4Rs?

Activity 1. How much waste does our school produce?

NOTE: You will be calculating the amount of waste produced by your school over the course of one year. In our demonstration calculations we have counted one year as being 52 weeks or 12 months. You will need to work out how many weeks/months your school is open for during the year to get an accurate measurement for your school.

Landfill Rubbish

1. How big is your skip? To measure the volume of the school's skip bin, get a 1 metre ruler or a measuring tape. Measure the length, the height and the depth in metres ( L x H x D = Volume m³). If you have more than one landfill skip multiply the volume by the number of bins. Be sure to check that all the skips are the same size and adjust figures accordingly.

2. How often is it collected? Ask the office when your skips are emptied. It is most likely to be every week or fortnight.

3. How full is the skip when it's collected? Estimate how full the skip is just before it is being emptied. Convert your estimate to a volume.

4. How many cubic metres of landfill waste are collected per month? Calculate how many cubic metres of waste are being collected per week and then work out the monthly volume.

Total volume of rubbish x how often it's collected per month = ____ m³ per month

5. How many cubic metres of landfill waste are collected per year? Multiply your monthly volume by 12 = ___________ m³landfill waste per year.

6. How many kilograms of waste is collected per year? Multiply your annual volume by 131 = ___________ kg's of waste per year.

Conversion factors - 1 cubic metre of mixed waste (not compacted) weighs 131 kg.

If the total volume of the MCG is 1,700,000 cubic metres, what percentage of the MCG does one year of waste at your school represent?

Paper and cardboard

1. What is the total volume of your paper recycling bins or skips? Measure the length, the height and the depth in metres ( L x H x D = Volume m³). If you have more than one recycling bin or skip multiply the volume by the number of bins.

2. How often are the paper bins/skips emptied? Find out when the bins are emptied. Most bins are collected every week or two weeks.

3. Check out how full the bins or skips are when they are being collected. If it's not near collection time, ask the school cleaner how full the bins usually are.

4. What is the volume of paper being collected per month? Volume in bins/skip x how often it's collected per month = ____ m³per month

5. How many cubic metres of paper is collected per year? Multiply your monthly amount by the number of monthly collections per year e.g. 12 = ____ m³per year.

6. How many kilograms of paper and cardboard is collected per year? Multiply your annual amount by 240 = ___________kg's per year.

TIP - Another way to measure volume is in litres. 1 cubic metre = 1000 litres.

Conversion factors - 1 cubic metre of paper and cardboard waste weighs 240 kg

Other recyclables

Conversion factors

1 cubic metre of mixed waste (not compacted) weighs 131 kg
A wheelie bin holds either 120 or 240 litres (or 0.12 or 0.240 cubic metres) - check your bins before making your calculations.

Food waste

Conversion factors

1 cubic metre of food waste weighs 200 kg
One bucket holds about 10 litres or 0.01 cubic metres

Green waste

Green waste includes leaves, grass clippings, light prunings etc.

Conversion factors - 1 cubic metre of mixed green waste weighs 64 kg

Special rubbish collections

Many schools have a hard rubbish collection once or twice year. Check with your rubbish collector whether this rubbish ends up in landfill or is sorted for recycling.

Conversion factors - 1 cubic metre of mixed waste (not compacted) weighs 150 kg

What is the combined total waste your school produces over one year?

Calculate the weekly totals for rubbish, paper and cardboard, other recyclables, food waste and green waste
Calculate the yearly total for special rubbish collections

If the total volume of the MCG is 1,700,000 cubic metres, what percentage of the MCG does the combined total waste for one year at your school represent?