Lesson Plan

• Describe how equilibrium is determined where quantity demanded equals quantity supplied.
• Explain the concepts of surplus and shortage as forms of disequilibrium.
• Draw and label disequilibrium situations on demand‑supply diagrams for both price above and below equilibrium.
• Interpret how market forces act to restore equilibrium after a surplus or shortage.
• Analyse the impact of a shift in demand or supply on the equilibrium price and quantity.

• Projector and screen
• Whiteboard and markers
• Graph paper or printed diagram worksheets
• Rulers and coloured pens
• Calculator (optional)
• Exit‑ticket slips

Begin with a quick poll: “What happens when a store runs out of a popular product?” Connect responses to the idea of shortage. Review the previous lesson’s definition of market equilibrium. State today’s success criteria: students will accurately draw disequilibrium diagrams and explain the forces that move the market back to equilibrium.

1. Do‑now (5'): Students complete a short worksheet identifying surplus vs. shortage from given scenarios.
2. Mini‑lecture (10'): Recap equilibrium, introduce the step‑by‑step method for drawing disequilibrium.
3. Guided practice (15'): Teacher demonstrates drawing a surplus (price > Pₑ) on the board; students replicate on graph paper.
4. Paired activity (10'): Pairs draw a shortage (price < Pₑ) and label all components.
5. Interpretation discussion (10'): Groups explain why prices will adjust, linking to market forces.
6. Shift analysis (10'): Brief exploration of demand/supply shifts using the provided table; students sketch new equilibria.
7. Exit ticket (5'): One‑sentence answer to “What signal does a surplus send to producers?”

Summarise how surplus and shortage are identified on a diagram and how market forces restore balance. Collect exit tickets as a quick check for understanding. Assign homework: complete a worksheet that requires drawing disequilibrium diagrams for two different price scenarios and explaining the resulting market adjustments.