At any moment, sunlight lights roughly half of Earth. A place turns into daylight and later into darkness as Earth rotates. The daily cycle takes about 24 hours. From the ground the Sun appears to move across the sky because we turn. This does not mean the Sun is stationary in every frame of reference. Safety: Use only a low-power battery torch. Never aim its beam at eyes. Do not use mains lamps or sunlight. Stop: Stop after one narrated cycle. No outdoor Sun tracking, dark room or long observation is required.

Materials: Paper; Pencil; Soft ball or folded paper Earth disk; Small piece of removable paper tape; Battery torch; paper-only fallback provided 1. Put a tape place-dot away from the ball’s poles. Mark an axis top and bottom. Put a battery torch about 50 cm away on a stable table, aimed at the ball. Keep enough room light for safe movement. 2. Hold the ball in one place with its axis upright for this simplified model. Turn it slowly so the dot moves from the unlit half into the lit half, through the lit half, then back into darkness. The torch stays still. 3. Draw sunrise, daytime, sunset and night snapshots. Shade each side away from the torch. At sunrise and sunset put the dot at the light boundary. Sizes, distances and spin speed are not to scale. 4. Add a west-to-east rotation label. Looking down from above Earth’s North Pole, this is anticlockwise. Explain why a ground observer sees the Sun’s usual daily path from east towards west. 5. Repeat one turn and narrate the dot’s cycle. Write about 24 hours beneath the complete turn, not beneath each snapshot. Done: Finish four shaded snapshots and a rotation-based explanation of the apparent solar motion. Proof: Keep the snapshots. Note who turned the ball and any supplied sunrise/sunset labels. Stop: Stop after one narrated cycle. No outdoor Sun tracking, dark room or long observation is required.