See the outdoor sound lesson for more sound activities (some loud and some need the space of outdoors).
During COVID, even if indoors, replace sound sandwich with laughing cup, to avoid students needing to blow through an instrument.
Indoors, choose a selection of these activiites:
Introduce the concept of sound with students making their own sound sandwich.
Help students figure out how the sound is made: the vibration of the elastic band is transmitted to molecules in the air, causing them to vibrate. This vibration of molecules travels through the air to our eardrum. In our ear the vibration is converted to a nerve signal that is sent to our brain, so we sense the vibration as a sound.
Use slinky to model how sound vibrations travel: Sound Vibration Model.
Explore the pitch of sound through sound with a ruler.
Show on a ukelele or other musical instrument how pitch can be changed by changing the length of a string/tube. Discuss other instruments that students play and how the pitch changes in them.
Sing a class song using the instrument, students accompanying on their sound sandwich.
Additional exploration of sound travelling through different materials with the sound through solids activity.
While students are experimenting, visit them to show them how sound travels through bones.
Note that the constant noise of this class builds the energy level of the students quite dramatically. Including the 'Sound through string' activity keeps things a bit less hectic as students' ears are blocked. Outside lesson also a good option.
Ruler vibrations too subtle/complex for younger grades - maybe switch out with elastic band sounds where they can see the vibration.
Stuff to try: http://science-notebook.com/sound01.html