Lesson Plan

• Describe the concept of a drainage basin and its boundaries.
• Explain the three pathways of water movement through a basin and the water‑balance equation.
• Analyse how topography, geology, land use and climate influence runoff and discharge.
• Calculate river discharge using Q = A × v and identify factors that modify it.
• Interpret hydrograph components and relate them to flood and drought hazards.

• Projector and screen
• Digital map of a catchment (GIS or Google Earth)
• Printed worksheets with basin diagram
• Hydrograph graph paper and calculators
• Whiteboard and markers
• Sample rainfall‑discharge data set

Imagine a single rainstorm causing a river to surge and flood downstream. Students should already know the basic water cycle and key river terminology. Today they will label a drainage‑basin diagram, calculate discharge and sketch a simple hydrograph, demonstrating mastery of the success criteria.

1. Do‑now (5 min): quick quiz on the water cycle and river terms.
2. Mini‑lecture (10 min): introduce drainage‑basin concept, divides, and show a cross‑section diagram.
3. Group activity (12 min): label a printed basin diagram, identify surface runoff, subsurface flow and groundwater pathways.
4. Demonstration (8 min): calculate discharge (Q = A × v) using sample cross‑section data.
5. Hydrograph workshop (12 min): plot discharge against time for a given storm, label baseflow, rising limb, peak and recession.
6. Formative check (8 min): exit ticket – one sentence explaining how basin characteristics affect flood risk.

We recap the key steps from defining a drainage basin to interpreting a hydrograph and its link to hazards. Students hand in their exit tickets and reflect on the lesson’s objectives. For homework, they will complete a worksheet that requires interpreting a hydrograph for a different catchment and suggesting mitigation measures.