Demonstrating a water catchment model
This activity reinforces, in a practical way, the knowledge students have gained through previous activities. This activity gives the teacher the opportunity to demonstrate how to construct a model catchment area prior to assessing the students’ models.
Earth and Beyond
3.3 Students collect information that describes ways in which living things use the Earth and the sun as resources.
4.1 Students recognise and analyse some interactions (including the weather) between systems of Earth and beyond.
Life and Living
3.3 Students describe some interactions (including feeding relationships) between living things and between living and non-living parts of the environment.
Systems, Resources and Power
SRP 3.1 Students make inferences about interactions between people and natural cycles, including the water cycle.
Students creating labels and a written procedure for constructing the model.
Creating the labels for the model (Extension activity).
Planning a catchment model.
Measuring the perimeter, area and capacity of the model. Using callipers to measure awkward and/or small lengths.
The materials listed are required if making the model indoors. The model could be constructed outdoors in an unused sandpit or garden bed. Materials may differ slightly.
You will need:
- large piece of plastic or tarpaulin
- load/supply of sand, soil, clay, gravel
- building blocks and the like to represent buildings
- small squares of cloth
- supply of dead twigs and small branches and the like to represent native vegetation
- weeds and the like to represent non-native vegetation
- piece of aluminium foil cut into a star shape, 4 cm across (to show the school’s position in the catchment).
You may have other ways of creating your catchment using:
- paper mache
- polystyrene foam
The important aspects are that the students create the catchment and that it is three-dimensional.
Give prior thought to the selection of the site for construction of the model. All students will want a clear view of the construction process.
Students can be given responsibility for bringing and removing the materials to/from the construction site.
If possible, select a site where you can leave the model for some time.
If you wish students to develop some of the materials (e.g. painting the twigs and branches) for the model, have them organised and completed before you begin the model.
If you wish to demonstrate erosion to the students, see "Additional learning" in this activity.
Time: 45-60 minutes
Inform the students you are going to demonstrate constructing a model of a water catchment area. Ask them why people make models and what their purpose is. Ask them if they have seen models before and where and what they think their purpose is. (At council chambers, shopping centre, shows, expos, in movies and computer games). Ask them to suggest a purpose for the model of a catchment area.
Explain to the students that the purpose of this activity is to demonstrate creating a model catchment and that they will be expected to create their own model at the end of the study of water catchments (if this is the option you wish to choose for a culminating activity).
If students are responsible for bringing and removing materials to or from the site organise them, ensuring they understand their responsibility and the relevant safety issues prior to moving to the site. You may need to set up some things beforehand to ensure the demonstration runs smoothly.
What to do.
- Create a space in your classroom or use an open area nearby.
- Lay the plastic or tarpaulin on the floor.
- Tip the wheelbarrow load of sand and or soil, clay onto the plastic or tarpaulin.
- Create a catchment. Use the materials in the following way:
- Building block = buildings
- Straws = pipes
- Squares of cloth = crop lands
- Twigs and small branches = native forests and vegetation (you may paint them)
- Weeds from the garden = non-native vegetation
During the construction, discuss with the students possible ways of creating a desired effect, e.g. how to construct the mountains. Students can assist in the physical creation of the model.
When you have finished the model, put an aluminium star in a position which best approximates the position of your school in the catchment.
Discuss human dependence on, and use of, the natural resources within the catchment.
Ask students to evaluate the model using the criteria you will be using when you assess their models at the end of the unit. For example:
- individual effort
- use of materials (choice of construction material)
- inclusion of catchment features (slope, water collection/storage site, vegetation, animals)
- overall effect.
Gauge, through questioning, their understanding of how to create a model of a water catchment area.
Nominate some students (or they may volunteer) to make labels for the model and to advertise it within the school community for others to come and view.
Students write the procedure for constructing the model.
Students begin to plan their own catchment model.
Gathering information about student learning
Sources of information could include:
- anecdotal notes on any student alternative conceptions or corrections of conceptions
- anecdotal notes on student participation and enjoyment of the activity.
Last reviewed 3 September 2010
Last updated 16 June 2008