• Quick retrieval from earlier learning (Find the part that vibrates to make the sound; Why we need light to see things). Students answer on mini whiteboards.
• Show answers together and note who needs support in the main task.

1. What vibrates to make the sound of a buzzing bee? (your vocal cords in your throat / the cone at the front / the strings / its wings) → its wingsPrompt: Which part moves back and forth when the sound is made?
2. What does a torch (flashlight) do in a dark cave? (It makes the cave warmer, so we see better. / It makes the walls give out light. / It makes our eyes stronger. / It gives out light that bounces off the walls so we can see them.) → It gives out light that bounces off the walls so we can see them.Prompt: Where does the light start, and where does it end up?
3. Put your fingers gently on your throat and hum. What do you feel? (nothing at all / something very cold / your heart stopping / a buzzing vibration) → a buzzing vibrationPrompt: Sounds are made by things moving back and forth.

• Ask the class to make a wave with a rope or slinky and describe what moves and what doesn't.
• Share the objective: Send messages with light and sound. Read the success criteria together.

• Work through the example out loud, saying why you do each step, not just what you do.
• Example: Does this signal use light, sound or both: a doorbell?
• Step 1: These signals are heard, so they work even if you cannot see them.
• Step 2: So the answer is: sound
• Answer: sound
• 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. Does this signal use light, sound or both: a pedestrian crossing that beeps and shows a green figure? (light / sound / both light and sound) → both light and soundPrompt: Do you see it, hear it, or both?
2. Why does a pedestrian crossing beep as well as show a green light? (because the light is broken / so people who cannot see well know when to cross / to make the cars go faster / to wake up birds) → so people who cannot see well know when to crossPrompt: Who might not see the green figure?

• 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 6 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. What message does this signal send: a car's flashing orange indicator on the left? (Stop and wait. / Playtime is over; go back to class. / There may be a fire: get out. / The car is about to turn left.) → The car is about to turn left.Prompt: Where would you meet this signal, and what should you do?
2. Your friend is across a noisy playground. Which signal will they notice best? (whispering her name / tapping a pencil quietly / humming softly / waving a brightly coloured flag) → waving a brightly coloured flagPrompt: Sound gets lost in a noisy place.

Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-1.