Breaking the Sound Barrier

Tom Brown and Kim Boehringer National Science Teachers Association
Type Category
Instructional Materials
Experiment/Lab Activity , Lesson/Lesson Plan , Activity
This resource, vetted by NSTA curators, is provided to teachers along with suggested modifications to make it more in line with the vision of the NGSS. While not considered to be “fully aligned,” the resources and expert recommendations provide teachers with concrete examples and expert guidance using the EQuIP rubric to adapted existing resources. Read more here.



Students explore and explain characteristics of sound through a series of hands-on learning centers and the sensory phenomena of waves produced by a "trashcan wave generator". Students sketch and explain what they discover at each of the centers which serve as the basis for teaching the concepts of amplitude and wavelength, and how waves can cause objects to move.

Intended Audience

Educational Level
  • Upper Elementary
  • Grade 4
Access Restrictions

Available for purchase - The right to view, keep, and/or download material upon payment of a one-time fee.

Performance Expectations

4-PS4-1 Develop a model of waves to describe patterns in terms of amplitude and wavelength and that waves can cause objects to move.

Clarification Statement: Examples of models could include diagrams, analogies, and physical models using wire to illustrate wavelength and amplitude of waves.

Assessment Boundary: Assessment does not include interference effects, electromagnetic waves, non-periodic waves, or quantitative models of amplitude and wavelength.

This resource appears to be designed to build towards this performance expectation, though the resource developer has not explicitly stated so.

Comments about Including the Performance Expectation
The "Tuning Fork" and "Rubber Band Guitar" learning centers ask students to record their data by drawing a sketch and explaining what is happening in these centers. This practice of having the students develop a model along with an explanation should be extended to the "First Phone" learning center and the trashcan generator experience. Evidence gathered from their investigations should be included in their explanations. As students will already have an initial understanding of vibrations and waves through an introductory discussion, it is likely that the models will depict the sound traveling in waves. In the tuning fork center and through the trashcan generator experience they will also be able to document that waves can cause objects to move as the tuning fork will cause the water to splash and the trashcan generator will enable them to feel the force of the wave. Differences in pitch experienced in the learning centers provides the opportunity to then introduce wavelength, and how higher pitches have shorter wavelengths and lower pitches have longer ones. Finally, the trashcan generator is a time to introduce the concept of amplitude, which is a measure of the strength or intensity of the wave, and enables the student to feel the force of the wave against their faces.

Science and Engineering Practices

This resource appears to be designed to build towards this science and engineering practice, though the resource developer has not explicitly stated so.

Comments about Including the Science and Engineering Practice
Students are asked to create a sketch along with an explanation to describe the phenomenon of sound that is being observed in two of the four investigations. It is recommended that this Practice be extended to all of the investigations. The inclusion of evidence in their explanation is also encouraged. Engaging students in a culminating project where they are provided a variety of different items (string, rubber bands, plastic cups, straws, index cards, etc.) and asked to CREATE their own model to demonstrate a sound wave is recommended to fully address this practice. An additional idea would be to download a free app such as n-Track Tuner and have students create a model that can hit a certain pitch.

Disciplinary Core Ideas

This resource was not designed to build towards this disciplinary core idea, but can be used to build towards it using the suggestions provided below.

Comments about Including the Disciplinary Core Idea
Through the learning centers students will understand that sound waves are produced by vibrating objects. The faster the vibrations, the higher the pitch of the sound. They will also learn how the properties of the objects, such as length, thickness, and tension will affect the pitch of the sound. Through these experiences, understanding can then be developed as to how amplitude and wavelength factor into these phenomena. The different pitches can be discussed in terms of wavelength and differences in amplitude can be discussed when comparing the water waves created by the tuning fork with the waves created by the trashcan generator. This resource from Bozeman Science is suggested to support their understanding of how differences in amplitude and wavelength affect sound:

Crosscutting Concepts

This resource is explicitly designed to build towards this crosscutting concept.

Comments about Including the Crosscutting Concept
Collectively, the investigative data will reveal that vibrating objects create sound waves, and that the faster the vibrations are, the higher the pitch of the sound is. They will also learn that the properties of the objects affect the pitch produced. For example, shorter objects (i.e., tuning fork, rubber band) will produce sounds with a higher pitch than longer ones. Patterns will also emerge in terms of amplitude and wavelength, with higher pitch sounds having shorter wavelengths, for example. These patterns in the data need to be made explicit during the post-investigation class discussion.

Resource Quality

  • Alignment to the Dimensions of the NGSS: This resource appeared in the January, 2007 edition of Science and Children, well prior to the creation of the Next Generation Science Standards. With the tips provided there is a strong alignment to the dimensions of the NGSS with grade-appropriate elements of the Practices, Disciplinary Core Ideas, and Crosscutting Concepts to support students in making sense of phenomena. More specifically, it provides students with the experiential understandings of sound from which to develop more abstract concepts of wave properties. It is recommended the trashcan generator be introduced as an anchoring phenomena, along with the focus question: What is sound and how is sound transmitted? It is also suggested that guiding questions identified in the resource be posed as driving questions for each of the investigations.

  • Instructional Supports: With the introduction of the trashcan generator as the anchoring event, this resource engages students in a meaningful scenario that provides students with a purpose for making sense of phenomena. It builds on students’ prior knowledge. There are multiple opportunities for students to represent their ideas in written form and through model drawing. There are also opportunities for them to express and clarify their understanding through the post-investigation discussion. The resource documents support for English Language Learners (ELL), including having students repeat and rephrase the main ideas to each other in their own words and allowing students to complete their journals in various ways. It is recommended that the teacher revisit the "hook" as students explore and make sense of the phenomenon. The focus question, "What is sound, and how does it travel?" could also be used to drive the investigations. All students may extend their learning by engaging in the following vibrating ruler and straw kazoo activity:

  • Monitoring Student Progress: There are multiple opportunities to assess the students formatively: through observation as they conduct their investigations, through the data recordings in their journals, and through class discussions. The paragraph explaining what they learned about sound at the end of the lesson could be used to provide summative assessment information. Perhaps the focus question posed in conjunction with the recommended anchoring phenomena could be used to drive the constructed response.

  • Quality of Technological Interactivity: This resource does not include a technologically interactive component. To integrate technology, the teacher might integrate the use of a virtual oscilloscope found at