This lesson delivers the strand's summative assessment, the Waste Rock Stockpile Investigation. Introduce the real problem with the slide deck: mining leaves piles of waste rock, and when it rains, acids and chemicals can wash out (chemical weathering and erosion), polluting soil and water. Show the animated comparison of an uncovered vs a covered pile.
Model the expectations: a fair-test plan (change the cover; observe/measure the run-off; keep the pile, water and method the same), a labelled design, a safety note, and an explanation that uses weathering and erosion ideas. Do not model a specific winning design.
Light-touch only (this is assessment): confirm the materials, the "rain" procedure, safety rules, and that each student completes their own planning sheet even if building in a group. Remind students to compare their result with the uncovered pile.
Students complete the Waste Rock Stockpile Investigation: Part A (plan the fair test), Part B (safety), Part C (labelled design, build, test and record vs the uncovered pile), and Part D (explain the result using weathering/erosion and propose an improvement). Consolidate with a short class share of which designs reduced run-off best and why.