A system refers to a set of interdependent elements and their relationships that together form a complex whole, and as a broad pattern provides a useful cognitive tool for understanding the world. Systems thinking gives structure to how we understand the behaviour of energy and matter, and the ability to find and understand connections and interdependence, and explore cause and effect.
How to understand Systems
Systems thinking covers a number of sub-patterns and habits, all generally relating to the practice of studying relationships between parts, and between the system and other systems. “Ecosystems” describe the interactions between organisms and their environment.
Connections and Relationships between Parts
Systems thinking requires you to think in terms of relationships and connections. Some parts can be dependent on others, and may even be interdependent, causality may be complex and cyclic rather than traditional “cause and effect”. The nature of relationships between parts and changes to them are a major factor in the behaviour of the whole system.
To simplify our models, we define boundaries to our systems (not always explicitly), and any interactions that cross the boundaries are seen as “inputs” and “outputs” of energy and matter. Boundaries are often muddy and hard to cleanly define, as reality is generally a lot more complicated than we can fit in our system.
Within systems we can identity subsystems, and then use the same methods to study them. This gives us a way of connecting scales – cells are nested within organs, organs within organisms, organisms within ecosystems, ecosytems within the biosphere, and similarly for human systems. Nested systems are a simplification, and sometimes network models are more useful.
Systems thinking includes many more interlinked sub-patterns than we can cover in detail here, such as growth and decline, feedback loops, networks, population dynamics, shocks and resilience. Some awareness of these patterns can help to link activities and lessons to system models.
How to teach Systems
Systems are not necessarily something that needs to be taught directly, but they are a powerful way of structuring discussions and investigations, and for gauging students knowledge. Frequently asking useful questions that explore relationships in systems is more important than getting the right answers every time, as it’s the habit of thinking and questioning that we aim to teach.
Students can be introduced to the systems concept during energy and matter tracing activities, and by engaging with their garden as an ‘ecosystem’ identifying living and non-living parts and using energy flow and matter cycles to draw connections and understand the relationships between them. This practice can then be extended to all ecosystems, and eventually human systems like their classroom or the city they live in.
Build capabilities and habits of mind
As students progress through the program, they do not necessarily need to be able to define the meaning of the word ‘system’ but we aim for them to develop the habit of mind of systems thinking, with the ability to look for:
- Relationships, networks and interdependence between parts of a system.
- The energy sources that drive a system.
- The types of materials cycling within a system.
- The material moving in and out of a system.
- Systems within systems (nested) and how they connect.
- Common patterns of system behaviour, like feedback loops, population dynamics, shocks and resilience.
- Teach systems opportunistically
Systems ideas can be taught through exposure to systems thinking in practice. There are many opportunities to do this, especially in a garden program. The important work of the teacher is linking real examples to systems patterns opportunistically, more than teaching systems in set classes.
Systems Lesson Examples
In the classroom:
- Ask students to describe ecosystems in places they have not been to, first making sure they know and remember a range of different ecosystems. Choose a place on the globe you and the students know enough about (maybe African savannah, Australian desert or reef, Malaysian Rainforest, Antarctica). Where is this? What type of ecosystem is this? What is the energy source that drives this system? (the sun!) How much input does it receive? What parts of the ecosystem are able to use that energy directly? (types of plants, phytoplankton) What parts of the ecosystem are dependent on others that use sunlight? (types of herbivores) What parts are dependent on them? (types of predators) What are the material inputs and outputs that create certain conditions in that ecosystem? (rainfall, subsoil, CO2, N etc).
- Apply the same methodology to other systems, like the city you live in. What are the parts? How are they connected? What is the main energy source? (eg. Fossil fuels, hydro, sunlight from agriculture) Which parts of the system are able to use or dependent on each energy source? What happens if there is a shock to the system or another system the city depends on? (eg. drought conditions reduce the wheat harvest, petroleum prices increase if availability declines).
In the garden:
- Define the garden ecosystem, its parts and their relationships. Look at energy flows and matter cycles into and out of the system. Frequently ask questions that explore relationships in the garden in order to develop a systems approach. Population dynamics can be explored when aphids buildup on plants then collapse once predatory ladybird larvae catch up, and reiterated when snails build up after a wet period and children feed them to the chickens. Positioning activities around watering the plants within the water cycle, and the small garden system placed within the broader water cycle. Ask what might happen if these relationships change, or explore what happens when relationships do change.
- Use play-based learning to explore the energy and matter requirements of human systems and the relationships and networks within and between them. Encourage students to design and construct a miniature fossil-fuel free village system. What are the main energy sources for your village? How will you ensure the energy and material requirements of your village and its members are met? Is your village resilient? How can you build-in resilience? What is its relationship with the surrounding environment and other communities?
The theme of Natural History includes Local Natural History, Evolutionary History and Food History. It provides you with a broad platform for contextualising energy flow and matter cycles whilst help students develop an authentic sense of place and perspective. Some examples of applying the Natural History theme are: Learning about photosynthesis and bio-geochemical cycles on our planet through exploring the history of life on Earth. Learning about life and society during the Gold Rush by looking at how energy flowed through those societies. Looking at the evolution of humans and human civilisation through the history of food and agriculture.