Pop Bottle Waves and Hair Dryer Ripples

Mary Ellen Kanthack
Type Category
Instructional Materials
Lesson/Lesson Plan , Activity , Experiment/Lab 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.



This is the first lesson in a series of lessons on waves. It is an exploratory lesson where students observe, draw and think about how waves are shaped, how they move and what creates them. The teachers creates a model using a plastic bottles with colored water inside. The students then make their own models using the materials and procedures set up by the teacher. Students observe and record the waves and how they change. Students also observe how a hair dryer creates ripples on water that the teacher models for them. Students then gather together to discuss their observations. The teacher creates a collaboration board as a means of recording their ideas/explanations around the speed of the waves and evidence to support these ideas from their observations and investigation.

Intended Audience

Educational Level
  • Grade 4
Access Restrictions

Free access - The right to view and/or download material without financial, registration, or excessive advertising barriers.

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
In this lesson the students recreate a model first demonstrated by the teacher using bottles and a cork to explore wave properties. The motion is created by the students "rocking" the bottles back and forth to a metronome. A teacher could modify this lesson to be more student driven by asking the students to use the model to create different size waves instead of outlining the procedure and rhythm of rocking to which they must follow. This could come after their initial observations. of a teacher-led model. Student-centered explorations will pique curiosity and questions that lead to deeper thinking and more focused observing when using the metronome. The videotaping is a effective strategy that allows students to go back and observe more closely the waves that were created. Vocabulary of amplitude and wavelength aren't explicitly used, but their concepts are being developed and expressed by the students in their own words, setting up potential for subsequent lessons to more directly address their terminology and concepts.

Science and Engineering Practices

This resource is explicitly designed to build towards this science and engineering practice.

Comments about Including the Science and Engineering Practice
This lesson, while more teacher guided, does allow for students to use models to describe and predict phenomena.This first lesson could be more connected to developing a model if students were given phenomenon or problem to figure out. In this lesson students are using a model demonstrated by the teacher. A suggestion might be to show students a video of waves in water ( a phenomenon) and asking them how this could be happening. Students could share their thinking about what they think is happening in the video and then the teacher might say "Now you are going to have an opportunity to model what might be happening. Students could be given the materials bottles, water, cork, food coloring and asked to develop their own model of what they were thinking. As mentioned in the PE section, it would be more effective to allow students time to explore the model first, before timing their rocking with the metronome. This exploration would enable students to then make predictions about the waves created to the different rhythms.

Disciplinary Core Ideas

This resource is explicitly designed to build towards this disciplinary core idea.

Comments about Including the Disciplinary Core Idea
The model using the bottles with colored water and a cork as well as the hair dryer blowing over water, are effective investigations of the edited core idea. The concept of no net motion in the direction of the wave is not addressed in this lesson.

Crosscutting Concepts

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

Comments about Including the Crosscutting Concept
The patterns the students observe are later used as evidence to support their explanations and understanding of wave properties. While later lessons that elicit students ideas and explanations are also more teacher directed, this first lesson gives students the opportunity to create their initial ideas about the phenomena. Students are specifically asked to identify the patterns they observed each time the metronome beat faster, and the patterns in the behavior of the cork as they waves sped up. They then used these observations as evidence in response to the prompt, "The faster the wave…" Students might be asked if they see patterns in their investigations and asked to describe them to each other in a scientist meeting trying to come up with a consensus explanation that they could use in their scientific explanations for what is happening. For example, the teacher might ask "How can you explaiin what is happening in the bottles. Make sure to include "patterns" as part of your explanation..

Resource Quality

  • Alignment to the Dimensions of the NGSS: This lesson provides students with the opportunity to develop and use the scientific practice of using models to make predictions about phenomena. Students investigate the core ideas of waves and their properties using this model. The patterns the students observe are later used as evidence to support their explanations and helps them to begin to make sense of these patterns. While the lesson is more teacher directed in terms of instruction, the opportunities are there for students to engage in 3 dimensional learning with some modifications that might include more student directed investigation into the core ideas using the pop bottle and hair dryer models and the introduction of the concepts of amplitude and wavelength as a way to describe the wave patterns.

  • Instructional Supports: The context of this lesson, the model and the phenomena it is demonstrating, does motivate students to engage in the core idea and practices. It also provides two different contexts for students to investigate the phenomena and then connect their explanation to their experiences. Because it is an introductory lesson it should be a means to elicit their prior knowledge, but it doesn't. Teachers could begin by asking students what they know about waves, where have they seen them before, and what have they noticed before introducing the model students will use to make waves. The use of videos enables all students to participate in the investigation of phenomena and allows the students to review as many times as needed what occurred during their investigation.

  • Monitoring Student Progress: Use of the video tapes, the collaboration board, data collection sheets, and student notebooks provide the teacher with direct and observable evidence of the students learning and development of the core ideas. The teacher is specific in eliciting students' ideas about patterns of wave behavior that were observed while using the models. The collaboration board at the end of the lesson allows students as well as the teacher to observe what evidence the students use to support their ideas and explanations. There is no explicit indication in the lesson of what the teacher is looking for in terms of evidence, but the questions posed at the end are designed to get at the core ideas and cross cutting concepts.

  • Quality of Technological Interactivity: The teacher has the students use video to capture their investigation of the phenomena of wave patterns. This technique allows students to go back and look more closely at the patterns and wave behavior in order to make sense of and explain what is happening. The evidence is right there for them to refer to and for the teacher to use as a means of formative assessment. Another suggestion might be to use the SloPro app for iPad as it would allow students to take high speed video and replay it in slow motion. It is a tool that can be very helpful in making observations.