Geography K–10 · Years 7–8
Contour lines from a model hill in a rising tank
Landscapes and landforms (ACARA Year 8 sub-strand) as the context; NSW Stage 4 focus area Landscapes and Landforms (2015 syllabus) and Landscapes and landforms (2024 syllabus); geographical tools. Every ACARA code listed here belongs to the Year 8 Skills strand and none to the Landscapes and landforms sub-strand: the practical draws, reads and communicates a map of a model hill rather than teaching a landform, so only Year 8 skills codes are listed.
This site has no interactive model of its own. Where a step or a material names a Concept Studio model, simulation or tool, it has not been built; an external simulation a step names (for example PhET) is not part of this site.
The idea
A contour is the line where a level surface meets the land, so raising water in fixed steps around a model hill draws the contour map of that hill.
What you need
- Clear straight-sided tank 30 cm × 20 cm × 15 cm with a ruler taped vertically outside
- A model hill of modelling clay (about 1 kg) with one steep face and one gentle face and a saddle, on a base that fits the tank
- Water jug; a sheet of clear acetate and a fine permanent marker; a photo from directly above
- Grid paper for the plan; ruler
How to do it
- Place the hill in the tank. Photograph from directly above with the acetate over the tank rim taped in place.
- Add water to the 1 cm mark. Trace the waterline onto the acetate from above (the first contour, 1 cm).
- Raise the water 1 cm at a time, tracing each waterline, until the hill is covered. Label each line with its height.
- Remove the acetate: it is the contour map. Copy it to grid paper at 1:1.
- Draw a straight line across the map from the steep side to the gentle side, read the heights where it crosses contours, and draw the cross-section.
- Compute the gradient of each face: height difference ÷ horizontal distance measured on the map.
What you should see
A contour map in which lines are close together on the steep face and far apart on the gentle face, with a saddle appearing as two rings pinching together. The cross-section drawn from the map is compared with a side photograph of the hill. Gradients from the map (for example 4 cm rise over 5 cm run = 0.8 on the steep face; 4 cm over 15 cm = 0.27 on the gentle face) are compared with direct ruler measurements on the clay.
What changes
This activity lists no variables to change, measure and keep the same.
Common misconceptions
Each of these ideas is wrong, and the activity is a chance to test it.
- Contour lines are paths people walk along.
- Contours close together mean a high place.
Safety card
Hazards
- water spill
Controls
- tank on a tray
Note
No chemicals or heat are used. The activity is run under the school risk-assessment procedure; RiskAssess (riskassess.com.au) holds templates for school practicals and fieldwork. The NSW Department of Education Chemical Safety in Schools package is not triggered.
Curriculum references
The NSW syllabus outcomes and Australian Curriculum v9 codes this activity supports. They are references, not a verified or complete curriculum alignment.
- Geography K–10 Syllabus (2015), NESA; current and taught in 2026, replaced from 2027. The outcome codes are not printed on the NESA landing page for this syllabus, which only links the document, so the url given is the syllabus document itself (geography-k-10-syllabus-2015.docx); the code and its outcome text were read in that document on 23 September 2026.GE4-7GE4-8
- Geography 7–10 Syllabus (2024), NESA; implementation from 2027, not yet taught; code read on this page on 22 September 2026GE4-TAP-01GE4-COM-01
- Australian Curriculum v9AC9HG8S02AC9HG8S03AC9HG8S06
Sources
The pages the author read to write this activity.