Before you begin this study, please participate in this activity below. This short learning experience will help you think about sound and how people perceive sound waves, as well as introduce the science concepts behind the engineering design of speakers that students created in this lesson. The technologies involved in the lesson include microphones that can capture sound and software that displays the sound.
Please study the graph below. Can you tell which speaker is a subwoofer (large size) and which is a tweeter (small size)?
- What was your reasoning behind deciding which speaker you picked for each line on the graph?
- Why would certain speakers produce different frequencies better than others?
Have you ever listened to a moving musical composition and yearned to discover the science behind the emotion? We are constantly bombarded by sounds every moment of every day. They come from many sources and affect us in varying degrees. By looking at how sound can be taught in physical science this unit helps students gain a greater understanding of this constant companion.
The text that follows presents a text/video-based case study from Michael Keiffer’s eighth-grade science classroom and was created to help students develop a basic understanding of sound waves and how waves interact with the physical world.
Although sound is taught many times throughout children’s education, the concepts still remain difficult to grasp. Looking deeply into the concepts of waves and sound, the use of visualizations, activities, and design projects can be used together and applied to deepen children’s understanding of waves and their properties.
A better understanding of sound waves and their properties will help students understand many other topics in science and mathematics. It is pertinent to get at these concepts early so that they can be correctly adapted and applied throughout their educational career.
In general, waves have three primary properties:
- Frequency: The frequency of a wave is often it vibrates.
- Amplitude: The amplitude of a wave is how far it vibrates from its resting position.
- Wavelength: Wavelength is the distance between each vibration.
Click on the link below to answer questions about wave attributes. Please return to this page when you finish.
Standards in A Framework for K-12 Science Education provides guidance for elementary science teachers for students understanding waves:
Common Core: Wave Properties
- Waves are regular patterns of motion.
- Sound can make matter vibrate, and vibrating matter can make sound.
- A simple wave has a repeating pattern with a specific wavelength, frequency, and amplitude.
- A sound wave needs to be transmitted through any type of matter.
Additionally, the Next Generation Science Standards created by the National Science Teachers Association recommends teaching sciences in the context of engineering design. Engineering design is the planning process that engineers go through to create a product or a solution to a problem. These proposed standards utilize engineering to enhance learning science using a real world application.
In relation to sound waves as taught in this lesson, frequency and amplitude are:
- Frequency: In sound waves, frequency is perceived by the human ear as pitch (how high or low the sound is).
- Amplitude: In sound waves, amplitude is perceived by the human ear as volume (how loud or quiet a sound is).
Many students at all levels of education have a number of alternate conceptions regarding sound waves. Teachers can help reduce these alternate conceptions by utilizing appropriate technology through the use of engineering design. A clear understanding of sound waves enables students to confidently explore many alternate forms of waves as they progress through their school years.
Click on the link below to answer questions about sound waves. Please return to this page when you finish.
Meet the Teacher
- Michael Keiffer
- Physical Science Teacher
- Baxton Middle School
I am an 8th grade physical science teacher at Baxton Middle School in central Virginia. I have been a science teacher for 27 years and have taught physical science, earth science, chemistry and some social studies to middle school and high school students. I enjoy inspiring my students with science and providing them a better understanding of the world around them.
My philosophy of teaching is driven by a hands-on approach. I believe that students are more connected with the content and that they should have a chance to explore the ideas and concepts being addressed in class. I believe that students gain a deeper understanding of the material if they have the chance to physically design and manipulate the tools that I provide for them. When I cover wave science, we dive into a lot of the basic terms and I am hopeful that they can come away with particular understanding of how waves interact with particles. I use various demonstrations and visualizations that I believe this gives the students a unique experience when understanding this difficult concept. It is important for students to learn about waves because it is related to various other topics in science and is a major part of the world that we live in.
Baxton Middle School was first opened in 1966 as a junior high school. Baxton has a strong athletic program as well as a 75% participation rate of students in afterschool activities. The total enrollment is 477 students and the student to teacher ratio is 16.25 to 1.
The school is comprised of 48.4% African American, 40.9% White, 6.7% Hispanic, and 4% Asian/Pacific Islander students. 15.1% of students speak English as a second language. 29.4% of the students are gifted and 14.7% are classified as special education students. This particular unit was spread across a variety of classes, each with very different dynamics. I feel as though it was well suited for all classes as it has a lot of depth, but gets at the major concepts of waves in a way that relates to the students.
The activity described in this case was the culmination of a five day unit on sound waves. The first four days were spent performing various activities designed to build a knowledge base of the properties of waves. My goal for this unit was to have students gain an understanding of waves, the terminology used to describe waves, and how wave science applies to the real world. I introduced these concepts of waves using physical and mixed-reality demonstrations. The physical activity was a giant pendulum with a paint bucket attached to the end that dispensed paint out the bottom. My students could actually see how a wave is formed with vibrating motion (the pendulum swinging back and forth). The paint then spilled out onto long chart paper that was pulled underneath the swinging bucket. This concept was then reinforced with a mixed-reality pendulum. Mixed-reality is a junction of something physical and something virtual. So in this case we developed a small pendulum that connected to a tablet computer that showed our wave on the screen as the pendulum moved back and forth, just like the chart paper in the paint bucket example.
This lesson occurred in three phases: Design, Build, and Test.
Click on the link below to answer questions about the strategies for teaching sound waves. Please return to this page when you finish.
I relied on technology such as die cutters (Silhouette), 3-dimensional computer design software (FabLab ModelMaker), computers and tablets and sound level meters. The die cutters automatically cut out shapes of all kinds on 2-dimensional mediums (paper, cardstock, etc.) when a file is sent to them almost like a printer. The pieces are precisely cut out and can be used for all kinds of projects from scrapbooking to creating scale models of objects. It was the first time that students got to use this type of technology for fabrication. The 3-dimensional design software or CAD (computer aided design) software gave students an opportunity to create objects on the computer with real dimensions and preview what their object is going to look like. This provided the students with the opportunity to use real software to design something that would come to life, just like an engineer would. The students then used this model on the software and sent it to the die cutter so that it could cut it out to the correct specifications set by the students so that they were ready to fabricate a working model. The students also used a sound level meter (see below for an example of one) to test the loudness or amplitude of their speaker. This allowed the students to capture an intangible concept and map it in relation to their speaker design. The sound level meter brought a reality to the idea of volume so that they could see what their speaker could do and how sound worked through their speaker.
The use of die-cutters, CAD software, computers and tablets, and the sound level meter to further understand sound waves aligns with the following ISTE National Educational Technology Standards for Students (NETS-S):
- Creativity and Innovation: Students demonstrate creative thinking, construct knowledge, and develop innovative products and processes using technology.
- Research and Information Fluency: Students apply digital tools to gather, evaluate, and use information.
- Critical Thinking, Problem Solving, and Decision Making: Students use critical thinking skills to plan and conduct research, manage projects, solve problems, and make informed decisions using appropriate digital tools and resources.
- Technology Operations and Concepts: Students demonstrate a sound understanding of technology concepts, systems, and operations.
Classroom in Action
Throughout the activity portion of the lesson, students utilized engineering design principles to design, build and test their own speaker to deepen their understanding of waves.
The design challenge students were given was to build a speaker. They could choose to build a woofer speaker that played low tones well or they could choose to build a tweeter speaker that played high tones well. Students were encouraged to discuss their design ideas within their group. As they agreed on a course of action they drew their design on sheets of paper with measurements outlining a design goal. The next step in the design process was to take those drawings and create a 3-dimensional model on a computer using provided software.
Click on the link below to answer questions about the first phase. Please return to this page when you finish.
After designing their speaker on the computer software, they used technology to fabricate pieces of their speaker. Using a mixture of glue and tape and provided materials, students created speakers out of cardstock.
Click on the link below to answer questions about the second phase. Please return to this page when you finish.
After completing the construction of their speakers, students then set out to determine whether their design met the desired outcome. They utilized an online tone generator and a sound level meter to accomplish this. The online tone generator produced varying tones (frequencies) through their speakers. The sound level meter measured how loud each of these tones were through the speaker. By entering this data into 2 spreadsheets students were able to clearly see the strengths and weaknesses of their design and create a line graph comparing different speakers.
Click on the link below to answer questions about the third phase. Please return to this page when you finish.
Michael speaks to the effectiveness of teaching sound waves through engineering design in a project based unit. He also describes how the practical, hands on approach in this unit engaged and motivated students throughout the learning process.