How to Deliver an Excellent IGCSE Demo Lesson

A demo lesson is a sample of your decision-making

The panel is not expecting you to finish an entire syllabus topic in twenty minutes. It is looking for a visible learning journey: a precise objective, a check of prior understanding, a well-modelled idea, meaningful student practice, responsive assessment and a credible next step. Your choices must fit the exact Cambridge or Pearson specification supplied in the brief.

Narrow the objective until it can genuinely be assessed. ‘Understand electricity’ is impossible. ‘Use the relationship V = IR to calculate an unknown value and explain one common unit error’ is observable. In English, ‘analyse language’ is vague; ‘select one phrase and explain how the writer’s verb shapes the reader’s impression’ creates a checkable performance.

Use a five-part micro-lesson

Design backwards from the final check. If students must answer an exam-style question independently at minute 18, what do they need to recall, see modelled and practise first? Build only those steps. Give the panel a one-page plan that names the syllabus, objective, prior knowledge, likely misconception, assessment evidence and contingency.

• Minute 0–3 — Diagnostic start: one question that reveals the prerequisite knowledge or misconception.
• Minute 3–8 — Explicit model: think aloud through one carefully chosen example and make success criteria visible.
• Minute 8–14 — Guided practice: students complete a parallel step while you question, sample and respond.
• Minute 14–20 — Independent check: an unfamiliar but achievable item aligned to the objective.
• Final minute — Evidence and next step: summarise what the responses show and state what you would teach next.

Show interaction even when the panel is silent

Ask questions that generate thinking, not theatrical participation. Give wait time, request reasoning and plan how you will sample answers. If adults are role-playing students, state the expected year group and prior knowledge. If nobody responds, do not panic: explain how you would use mini-whiteboards, a poll, hinge question or paired explanation in a real class, then proceed with prepared response samples.

Technology should remove friction, not become the performance. One clear diagram, visualiser or annotation can help; six apps cannot. Bring an offline version of essential materials. A teacher who can continue after the internet fails demonstrates stronger classroom readiness than one whose lesson depends on an animation loading.

Avoid the five common demo failures

The most frequent failures are an objective that is too large, excessive teacher talk, activities with no evidence, inaccurate exam-board language and an ending that simply runs out of time. Rehearse with a timer and cut content rather than speaking faster. Check every scientific term, worked answer and mark-scheme phrase.

After the demo, expect reflection questions. Name one thing that worked, support it with observed evidence, and identify one change you would make. Thoughtful adaptation is not an admission of incompetence; it is evidence that you understand teaching as a cycle of planning, evidence and response.