Artifacts A and B represent student recordings (written or drawn) of who or what they thought was making the sound(s) that they could hear while on the nature walk. These artifacts - from the same class period - indicate many of the same sounds, though some are depicted differently. In particular, note how Artifact A has written the word “sirens” while Artifact B has a drawing of the sounding ambulance siren and note how Artifact A identifies “leaves” and “wind” (perhaps related), while Artifact B connects “wind” to “air.”

The video of Artifact C – from a different class period – identifies a bird creating a chirping sound. When the teacher asks “where is the sound coming from?,” one student introduces the idea of a potential mechanism by which sound moves by “bouncing over here,” and terms it a “bounce wave.” As the discussion continues, students pick up this provisional idea of the sound “bouncing” as it moves, with two students suggesting that maybe the sound bounces off of a nearby tree (and its leaves and branches). Note how the idea of “bounce” is taken up in the subsequent discussion but not the idea of “wave.”

This discussion has elicited some initial ideas about how sound might move, which is related to the disciplinary core ideas PS4.A on wave properties. Note that the Grade 1 standard 1-PS4-1 focuses on local movement (i.e. vibrations) serving as the cause (and the effect) of sound, while the Grade 4 standard 4-PS4-1 includes a more detailed understanding of how sound waves propagate through a medium.