Use only the teacher-provided source brief below. Design a 40-minute Grade 7 lesson on shadow formation, not the whole chapter. Give goals, exact timings summing to 40, predict-test-explain steps, four rotating respectful participation roles, safe cool-white-LED props and a check for understanding. No lasers, flame or direct sunlight. If evidence is missing, say so. Keep the transparent-object faint-shadow qualification. Cite printed pages for claims. Do not invent classroom results.
SOURCE BRIEF: [paste source-brief content here]
Teacher checks source accuracy, suitability, safety and timing before use.
