Sound Experiments for Kids: Can You See a Sound?
By Ahmed, founder
Sound is invisible, which makes it hard for young children to think about. The trick is to make it visible, and a few simple experiments do exactly that. By the end, your child can tell you the big idea of the whole topic: every sound comes from something shaking back and forth.
1. The jumping-rice drum
Stretch plastic wrap tight over a mixing bowl and hold it in place with a large rubber band. Sprinkle a few grains of uncooked rice on top. Now bang a metal pot with a spoon near the bowl, or hum loudly beside it.
The rice jumps. Sound travels through the air as vibrations, and the plastic wrap shakes with them. Louder sounds make the rice jump higher. Try different sounds and let children say which one makes the rice dance most.
2. The rubber-band box
Stretch two or three rubber bands over an open box, such as a tissue box or shoebox. Pluck one gently and look closely: the band is a blur. Touch it lightly, and the sound stops. That is the moment kids realise the sound was the shaking.
3. The twanging ruler
Hold a ruler flat on a table with half of it hanging over the edge. Press down with one hand and twang the overhanging end with the other. You’ll hear a buzzing sound and see the ruler vibrate. Now slide the ruler so more of it hangs over the edge, and twang it again. The sound gets lower and the shaking slower.
4. High notes and low notes
This experiment answers “why are some sounds high and some low?”
Rubber-band guitar. Put one thick band and one thin band on a box, about the same length. Pluck each. The thin band makes a higher note than the thick one. Now stretch a band tighter by pulling it over a pencil bridge, and notice the pitch rises.
Bottle notes. Line up empty plastic bottles with different amounts of water. Blow across the top of each. The bottle with the least water, which holds more air, sounds lowest. The one with the most water sounds highest. (If you tap the bottles instead of blowing, the pattern flips. Tapping makes the water and glass vibrate, so more water means a lower note. Have children discover this and ask why.)
The rule that comes out of all of these:
- Fast shaking makes a high note.
- Slow shaking makes a low note.
Our lesson How do you make a high note or a low note? builds both instruments and helps children state the rule in their own words.
Ask these questions
- What do you see when something makes a sound?
- What happens when I touch it?
- Which one is louder? Which is higher? Are those the same thing?
Loud and high are different. Loudness is how big the vibration is. Pitch is how fast. Young children often mix these up, and that’s a good conversation.
A gentle experiment with your own voice
Put your fingertips lightly on your throat and hum. You can feel the buzz. Hum a high note and then a low note and notice what changes. Then stop humming, and the buzz stops.
More sound activities
Start with Can you see a sound? and try Can a string carry your voice?, where children build a cup-and-string phone and test whether a tight string works better than a loose one. All three lessons are in the Sound: Can You See a Sound? unit.
Safety
Keep rubber bands away from faces and eyes. Don’t blow bottles back and forth between people. Clean bottle tops before sharing.
Keep going
Sign up for three full lessons as printable PDFs, free. You can also browse by grade in the library or find more family experiments on our parents page.