Make a mini worm farm
Year level
Middle Primary to Lower Secondary year level with a simplified activity for younger students
and an extension activity listed at end of lesson plan.
Lesson description
Students make their own mini worm farms out of empty plastic bottles to observe worms and
study their behaviours.
In this lesson students will become aware:
 that worms are one of nature’s best recyclers
 that composting worms recycle fruit, vegetable and paper scraps into worm castings
and worm tea
 that worm castings and worm tea are full of nutrients and can be used as fertiliser to
help grow vegetables and other plants
 of how to design a mini worm farm that can be used to recycle household organic
waste.
Curriculum links
Years 3 and 4
Investigate food and fibre production and food technologies used in modern and traditional
societies (Design & Technologies - ACTDEK012)
Year 4
The sustainable management of waste from production and consumption (Geography ACHGK025)
Living things, including plants and animals depend on each other and the environment to
survive (Science - ACSSU073)
Years 5 and 6
Investigate how and why food and fibre are produced in managed environments (Design &
Technologies - ACTDEK021)
Year 6
The growth and survival of living things are affected by the physical conditions of their
environment (Science - ACSSU094)
Year 7
Interactions between organisms can be described in terms of food chains and food webs
(Science - ACSSU112)
Science understanding influences the development of practices in areas of human activity
such as industry, agriculture and marine and terrestrial resource management (Science ACSHE121)
Brisbane City Council
Rethink Your Rubbish Lesson Plan: Organic Recycling – Mini Worm Farm
Years 7 and 8
Analyse how food and fibre are produced when designing managed environments and how
these can become more sustainable (Design & Technologies - ACTDEK032)
Materials
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1 x two litre clear, plastic soft drink bottle
1 x one litre or 600ml litre bottle
Scissors
Water
Half cup small gravel, for example: aquarium gravel
Soil (or moist worm castings if available) – approximately two cups
Sand – approximately two cups
Small fruit and vegetable scraps (worms will eat most fruit and vegetables, but avoid
citrus fruit, onions, garlic and chilli)
Newspaper
Back plastic bag such as a bin liner or black cloth
Compost worms (can be obtained from large hardware stores or from a working
worm farm) or garden worms
Fact sheet: ‘Worm farming’ (available on Brisbane City Council’s website)
Poster ‘What worms like to eat’ (available on Council’s website)
Procedure
1. Cut the top off the larger bottle.
2. Half fill the smaller bottle with water and place inside the bottom half of the larger
bottle. This will help to keep the worm farm cool and will ensure that worms are
closer to the outside of the larger bottle and therefore, more visible.
3. Put a layer of gravel into the space between the two bottles until it has formed a layer
of about two centimetres.
4. Add alternating layers of soil and sand starting with the soil. Each layer should be
about two centimetres thick. Continue until worm farm is almost full and ensure that
last layer is soil.
5. Moisten worm farm with some water.
6. Before adding worms draw a picture of the worm farm and label all the layers.
Alternatively, you can mark the layers on the outside of the bottle using a permanent
marker. This will then enable you to the changes that occur over time.
7. Add a handful of compost worms.
8. Add about one tablespoon of chopped up fruit and vegetable scraps then cover with
some damp newspaper. (Refer to ‘Worm farming’ fact sheet and ‘What worms like to
eat’ poster for more information).
9. Worms do not like the light so cover worm farm in black plastic or cloth and place in a
cool sheltered place.
Brisbane City Council
Rethink Your Rubbish Lesson Plan: Organic Recycling – Mini Worm Farm
10. Every day take off the cover and observe the worms. Note changes to food scraps
and to the layers. You should be able to observe how worms have moved through
soil from changes to the layers. Moisten worm farm if it becomes too dry.
11. Continue observations until food scraps have been converted into worm castings.
12. Return earth worms to soil or compost worms to the school worm farm.
Simplified activity
Teacher sets up one mini worm farm for the class to observe worms over a period of three
days
Extension activity
Carry out an experiment to observe what type and size of fruit and vegetable scraps are
consumed the fastest and the slowest. Ensure all conditions are the same except for the
food scraps. Food scraps can be hard, for example, carrot for one mini worm farm and soft,
for example, banana for another farm. To extend this activity further blend the hard food and
soft foods for two farms and leave the food in large chunks for another two farms. Observe
and record results.
Brisbane City Council
Rethink Your Rubbish Lesson Plan: Organic Recycling – Mini Worm Farm