Lesson Plan

• Describe the concept of consumer surplus and how it is measured.
• Explain why consumer surplus is important for welfare analysis and policy evaluation.
• Calculate consumer surplus using graphical and algebraic methods.
• Analyse how price changes, demand elasticity, and government interventions affect consumer surplus.
• Compare consumer surplus with producer surplus to assess overall market efficiency.

• Projector or interactive whiteboard
• Slide deck with demand‑curve diagram
• Calculator worksheets for CS calculations
• Graph paper and rulers
• Handout summarising CS definition, formula and key points

Begin with a quick poll: “If you could pay up to £100 for a gadget but bought it for £60, how do you feel?” Connect this to prior knowledge of willingness to pay. Explain that today’s success criteria are to define consumer surplus, illustrate it graphically, and calculate it accurately.

1. Do‑now (5’) – short quiz on willingness‑to‑pay concepts.
2. Mini‑lecture (10’) – definition, formula, and graphical illustration of consumer surplus.
3. Guided practice (15’) – paired worksheet solving the example (P = 100 – 2Q, price £40) and drawing the CS triangle.
4. Class discussion (10’) – significance for welfare, policy evaluation, and comparison with producer surplus.
5. Application activity (10’) – analyse a tax scenario on a given demand curve and predict the change in CS.
6. Check for understanding (5’) – exit ticket: one‑sentence definition of CS and a quick CS calculation for a new price‑quantity pair.

Summarise that consumer surplus measures the extra benefit consumers receive when market prices are below their maximum willingness to pay, and that it is a key welfare indicator. Collect the exit tickets to gauge individual understanding. For homework, assign a worksheet that requires students to calculate both consumer and producer surplus for two different market scenarios.