• Quick retrieval from earlier learning (Light sources and seeing). Students answer on mini whiteboards.
• Show answers together and note who needs support in the main task.

1. Is a computer screen that is on a light source? (light source / not a light source (reflects light)) → light sourcePrompt: Does it make its own light, or does light bounce off it?
2. Why should you never look directly at the Sun? (It makes you sneeze / Its light is so strong it can damage your eyes / It is not bright / It will go out) → Its light is so strong it can damage your eyesPrompt: Even sunglasses are not safe for staring at the Sun.
3. Light: which statement is NOT true? (Light travels in straight lines. / The Moon shines by reflecting sunlight. / A mirror is a light source. / The Sun is a light source.) → A mirror is a light source.Prompt: Does the Moon make its own light?

• Ask the class to make a wave with a rope or slinky and describe what moves and what doesn't.
• Share the objective: Shadows and transparent, translucent and opaque materials. Read the success criteria together.

• Work through the example out loud, saying why you do each step, not just what you do.
• Example: Is a thin cotton sheet transparent, translucent or opaque?
• Step 1: Translucent materials let some light through, but you cannot see clearly through them.
• Step 2: So the answer is: translucent
• Answer: translucent
• Pause after each step and ask a student to say what comes next.

• Do these together. Students try each step on whiteboards before you reveal it.
• Use the hints as prompts rather than giving the answer.

1. Is aluminium (aluminum) foil transparent, translucent or opaque? (transparent / translucent / opaque) → opaquePrompt: Can you see clearly through it, see a blur, or see nothing at all?
2. Why does a shadow have the same shape as the object? (Light travels in straight lines past the edges of the object / Shadows copy objects on purpose / Light bends around the object / The object is a light source) → Light travels in straight lines past the edges of the objectPrompt: Picture straight rays from the torch to the wall.

• Students work on the student sheet. Circulate and check the first two answers of every student early.
• Students who finish: write a question of their own for a partner, with the answer.

The 8 questions are on the student sheet below, with answers in the key.

• Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.

1. Which material is translucent? (cling film (plastic wrap) / tracing paper / a metal tray / clear glass) → tracing paperPrompt: Hold each one up to a window in your mind.
2. At what time of day is your shadow shortest? (it is always the same / early morning / late evening / around midday, when the Sun is highest) → around midday, when the Sun is highestPrompt: Where is the Sun at midday?

Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-3.