Students can be instructed step by step on how to make the sound sandwich.
Or, they are given a model at each table group to replicate - they need to use skills of careful observation and small manipulations.
Make the sound sandwich as follows:
Loop the wide rubber band around one of the large popsicle sticks.
Push the coffee stir stick piece under the rubber band, near the end of the popsicle stick.
(Optional addition: Lay the small popsicle stick over the rubber band, near the other end of the popsicle stick.)
Lay the second large popsicle stick over the first, sandwiching the coffee stir stick (and small popsicle stick if used) between them.
Wrap the small rubber bands around the ends, to strap the large popsicle sticks together.
Blow through the large popsicle sticks to make the rubber band vibrate (making sure not to get it wet with your tongue).
(Optional if part of model: Move the small popsicle stick nearer or further from the centre of the sound sandwich, to change the tone of the sound.)
Once they have made it and figured out how to make a noise, ask how they think the noise is made (and how we hear it).
(Blowing makes the band vibrate, which makes air molecules vibrate. The vibration of air molecules spreads out and moves to our ears where it causes the vibration of our ear drum, which leads to the stimulation of neurons in our inner ear.)
Then add nuances of the noise maker:
The sound can be changed by blowing harder or softer (makes the band vibrate at different frequencies, therefore producing a different pitch).
Can you make a sound by sucking air through it?
Detailed instructions at:
https://www.exploratorium.edu/snacks/sound-sandwich
