Stage 3 – STEM Activity 10
Wormy world
Description of activity
Students will observe the structural and behavioural characteristics of earthworms and design and build a worm habitat or worm farm.
This activity could take approximately 2 hours to:
- observe and describe the structure and behaviour of worms
- research the habitat requirements for a worm farm
- design a worm farm
- build and establish a worm farm.
It is advisable that this activity be carried out in groups of 2 or 3 students.
Context
Students have been exploring the way in which living things are suited to the environment in which they live. They may have been studying ways of increasing the sustainability in our use of our environment.
Outcomes
Skills
ST3-5WT plans and implements a design process, selecting a range of tools, equipment, materials and techniques to produce solutions that address the design criteria and identified constraints
ST3-4WS investigates by posing questions, including testable questions, making predictions and gathering data to draw evidence-based conclusions and develop explanations
MA3-1WM describes and represents mathematical situations in a variety of ways using mathematical terminology and some conventions
Knowledge and understanding
ST3-10LW describes how structural features and other adaptations of living things help them to survive in their environment
ST3-11LW describes some physical conditions of the environment and how these affect the growth and survival of living things
ST3-14BE describes systems in built environments and how social and environmental factors influence their design
ST3-15I describes how social influences impact on the design and use of information and communication systems
ST3-16P describes systems used to produce or manufacture products, and the social and environmental influences on product design
MA3-6NA selects and applies appropriate strategies for multiplication and division, and applies the order of operations to calculations involving more than one operation
MA3-9MG selects and uses the appropriate unit and device to measure lengths and distances, calculate perimeters, and converts between units of length
Resources
- Empty, 2L soft drink bottles with lids, newspaper, implement for making small holes in the base of the bottle, craft knife to cut plastic, white card, string, trowels, gravel, sand, potting mix, vegetable food scraps, earthworms
- Magnifying glasses, torches, disposable vinyl gloves, rulers.
Work, health and safety
- Check relevant Work, health and safety guidelines.
- Check relevant animal care and welfare guidelines.
- Ensure that students wash their hands before and after handling earthworms.
- Be aware of any students who may have allergies to soil.
- Students may wish to wear gloves rather than handle the earthworm or soil.
Evidence of work for assessment purposes
- Labelled, scale diagram of an earthworm and notes on adaptations
- Design plan for the bottle worm farm
- Photograph of the bottle worm farm.
STEM teaching and learning activities
- Students use a magnifying glass to observe a single earthworm placed on a white card. Students note, by observing the earthworm:
- the gross structure of their body (what can be seen with the naked eye)
- the fine structure of their body (greater detail seen with the magnifying glass)
- how they move
- their reaction to light.
- Students use a piece of string to measure the:
- relaxed length of the earthworm’s body
- extended length of the earthworm’s body
- contracted length of the earthworm’s body
- Students draw a diagram, taking up half an A4 page, of the earthworm’s body, labelling its features. Research can be carried out to find the names of the different structures of the earthworm’s body. Students provide constructive feedback on the diagrams (see Austin’s Butterfly)
- Students place their worm in the container of soil so that it can soon be transferred into the worm farms.
- Students measure the length of their diagram and compare this to the relaxed body length measured. As the diagram will be larger than the actual earthworm the calculation is:
- When this calculation has been done the resulting answer ‘A’ can be shown as A:1 on the diagram, indicating the scale.
- Students determine the amount of extension and contraction the earthworm’s body can undergo. This can be noted near the diagram.
- Students carry out research to find the adaptations that enable earthworms to survive in their environment. These adaptations may be structures and behaviours. Note the findings of their research on the same sheet of paper as the scaled, labelled diagram of the earthworm.
- Students carry out research to design and construct a worm farm in a bottle. Direct students to use blogs to carry out this research. A wide variety of methods and hints for improvement are available via blogs.
- Students discuss the similarities and differences in using books, articles found by using Google, and blogs. The discussions should address the following questions:
- Which source of information is the easiest to use? Why do you think so?
- Which source of information is the most helpful? Why do you think so?
- Which source of information is the most accurate? Why do you think so?
- Students decide on their design plan and record it. Explain why the different elements used to construct the worm farm were chosen and their effect on the worm’s environment.
- Students construct their worm farm. The worm farms can be observed and maintained at school or at home, providing compost for the home or school gardens.
- Students discuss the value of recycling food scraps to make compost.
Vocabulary list
Adaptation – a structure or behaviour that helps an organism survive in its environment
Biodegradable – material that can be broken down by living organisms, over time
Compost – decayed organic matter used as fertiliser for growing plants
Environment – the combination of all of the physical, chemical, and biological factors in which an organism lives or operates
Scale – the amount by which a drawing of a real object is enlarged or reduced.
Key inquiry questions
Why use a piece of string to measure the earthworm’s body?
One way to measure the length of something that is not perfectly straight is to place a piece of string along the actual contours of the body and then measure the length of the string.
How can you determine the scale of a diagram?
The scale of a diagram is how much the diagram has been enlarged or reduced from the real object, eg the actual length of an earthworm may be 10cm. If the diagram that is drawn is 20cm long, the diagram is two times larger than the actual object or the scale is 2:1.
Why are animals adapted to their environments?
Living things have characteristics that help them survive in their environment. If they do not have these characteristics they will die. Thus all organisms are adapted to their environment.
If the environment changes, due to human or natural influences, the organisms that live in that region may not survive because their structures and/or behaviours no longer help them survive, eg the polar bear. Individual organisms cannot adapt. They cannot suddenly develop new structures or behaviours that will help them survive. Some individuals may, by chance, have some structure or behaviour that helps them survive in this new environment. If they survive long enough to reproduce, their offspring may have inherited these adaptations and they too will survive and reproduce until the surviving species have these adaptations. In this way a species can adapt to changes in the environment, over many generations, but individuals cannot.
Additional information
The following statements outline some common preconceived ideas that many students hold, which are scientifically inaccurate and may impede student understanding.
Adaptation is something that living things can do
The word ‘adaptation’ is a noun, not a verb. An adaptation is a structure or behaviour that helps an organism survive in its environment, eg the white, thick fur of a polar bear helps it survive in the Arctic environment as it provides warmth and camouflage. In this sense it is an adaptation. As the Arctic ice melts, due to a warming environment, the warmth provided by the thick coat is no longer an advantage and may be a disadvantage due to over-heating. The camouflage becomes less useful due to the shrinking ice mass. The polar bear cannot change its fur covering. It is now an endangered species due to environmental change.
Support materials
- There are many substances that, when diluted and poured on a grassy area, will encourage worms to come to the surface, for example soap free teatree oil dog shampoo, mustard or potassium permanganate (also called Condy’s crystals).
- YouTube video: The amazing world of earthworms
- YouTube video: Worms are wonderful
- The life in dirt: the importance of soil
- Growing an organic edible garden
- YouTube video: Austin’s Butterfly on giving specific feedback
Diversity of learners
For extension
- This activity could result in building a worm farm or compost heap for the school’s use.
- Investigate the differences between ‘dirt’ and ‘soil’.
Review
By completing this STEM activity your students have the opportunity to investigate the relationship between structure, function and adaptation to the environment. These concepts are further developed in Science Stages 4 and 5 and biology. Students are engaging in sustainable processes and the ways in which these processes can affect the environment.
Students design and construct a worm farm, using recycled materials and explore different ways that information that they use has been provided.
NSW Government