• 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 voice? (the stretched skin on top / the strings / the metal triangle / your vocal cords in your throat) → your vocal cords in your throatPrompt: Which part moves back and forth when the sound is made?
2. What does a torch (flashlight) do in a dark cave? (It makes our eyes stronger. / It makes the cave warmer, so we see better. / It makes the walls give out light. / 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. Which part of a drum must you hit to make a sound? (the stretched skin / the air around it / the strap / the floor under it) → the stretched skinPrompt: Which part can wobble?

• 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: an ambulance with siren and flashing lights? (light / sound / both light and sound) → both light and soundPrompt: Do you see it, hear it, or both?
2. Your friend is across a noisy playground. Which signal will they notice best? (humming softly / tapping a pencil quietly / waving a brightly coloured flag / whispering her name) → waving a brightly coloured flagPrompt: Sound gets lost in a noisy place.

• 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. Ships at sea at night watch for a lighthouse. What message does its light send? (Danger: rocks or land are near here. / The sea is warm today. / Fish are nearby. / It is time for dinner.) → Danger: rocks or land are near here.Prompt: Why would a ship need to know where the coast is?
2. What message does this signal send: three short blasts on a whistle repeated? (There may be a fire: get out. / I need help. / Playtime is over; go back to class. / The car is about to turn left.) → I need help.Prompt: Where would you meet this signal, and what should you do?

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