Lesson Plan

• Define Price Elasticity of Demand (PED) and explain its economic significance.
• Calculate PED using the percentage‑change formula.
• Interpret PED values to classify demand as elastic, unit‑elastic, inelastic, perfectly elastic or perfectly inelastic.
• Identify key factors that influence the magnitude of PED.

• Projector and screen
• Whiteboard and markers
• Printed handout of PED value table
• Calculator worksheets
• Graph paper and rulers
• PowerPoint slides with example calculations

Start with a quick poll: “What would happen to your coffee purchase if the price rose by 20%?” Connect responses to the law of demand, then state that today students will measure that responsiveness using PED. Success criteria: students will be able to define, calculate, and interpret PED.

1. Do‑Now (5'): Students write one example of a price change they’ve experienced and predict the quantity response.
2. Mini‑lecture (10'): Define PED, present the formula, and show the PED value table.
3. Guided Practice (10'): Work through a sample calculation on the board using provided data.
4. Interpretation Activity (10'): In pairs, classify calculated PED values as elastic, unit‑elastic, etc., and justify.
5. Factors Discussion (10'): Think‑pair‑share on how substitutes, income proportion, necessity, and time affect PED.
6. Diagram Sketch (5'): Students draw a demand curve highlighting elastic, unit‑elastic, and inelastic segments.
7. Exit Ticket (5'): Write the definition of PED and one real‑world example of an elastic good.

Review the definition, formula, and interpretation of PED, checking the exit tickets for understanding. Assign homework: complete a worksheet calculating PED for three different products and explain the factors influencing each result.