These artifacts represent a range of student thinking at the end of this unit. 

Artifacts A and B show evidence that students are connecting the idea of “vibration” to the production of sound, and that sounds can be used to communicate at a distance. Artifact A, in particular, demonstrates an understanding that a vibration is the repeated motion of an object; perhaps this connection is clearer for the student given that their choice of instrument - a maraca - makes the motion easier to observe, whereas the piano keys (Artifact B) does not have an easily observable vibration. For the latter, the implicit link would seemingly be to the vibration of the tuning fork and the movement it caused when placed in water during the sound centers task.

In contrast, Artifacts C and D represent student thinking where the focus remains at a general description of the object. Both students attribute the cause of the instrument’s sound to the matter involved (i.e. balloon, air). While these are accurate observations, they do not reach for the causal story by which the squeaky sound is produced: the movement of the balloon material vibrating as the air quickly passes through the opening. While Artifact D mistakenly attributes a voice box to the balloon instrument, this connection to the production of animals sounds allows an opportunity for a teacher to extend this student’s thinking by posing a question that helps connect what the student feels (i.e. observes) with their fingers on their voice box and what the student feels (i.e. observes) with their fingers as air passes out of the balloon.