Waves, Energy, and Information March – May

Scientists all over the world seek to explain the patterns that different animals use to communicate. Within the animal kingdom, bottlenose dolphins are a particularly intriguing example of animals who use patterns in communication. Recent research has revealed that bottlenose dolphins use signature whistles—whistles with patterns of pitch changes that are unique to each dolphin. These serve as a form of identification for individual dolphins, and dolphins learn to recognize these whistles at a young age. In this unit, students take on the role of marine scientists investigating how bottlenose dolphin mothers and their calves in the fictional Blue Bay National Park use patterns of sound to communicate across distances, which serves as the anchor phenomenon for this unit.

To learn about important characteristics of sound and how sound travels through materials, students engage with several models of sound waves. These models, including an interactive digital simulation, physical models, and visual representations, support discovery and understanding of how dolphins use sound to communicate. These models, as well as informational text and firsthand investigations with sound, help students visualize things that are not possible to see: how sound waves travel at the particle level and how a sound’s volume and pitch correspond to the amplitude and wavelength of the sound wave. Students apply what they learn from their investigations to write a series of scientific explanations detailing how dolphins are able to communicate using sound. In the last chapter of the unit, students consider a new anchor phenomenon as they broaden their understanding of patterns in communication by investigating the patterns that humans use to communicate across distances.

Why?

Exploring patterns in communication enables students to see how waves, energy, and information play roles in their everyday lives. It allows students to engage deeply in essential disciplinary core ideas about sound waves and information technologies. Many students are fascinated by animal communication, and the unit’s context of investigating dolphin communication motivates a broad range of students to learn physical science. In addition, humans are surrounded by sounds, but the mechanics of sound are invisible and often misunderstood. Students may have heard that sound is a wave, but they may not know what that really means. Understanding what waves are and how sound energy travels provides a strong foundation for understanding more advanced concepts in physical science.

The concepts of waves, sound energy, and patterns in communication are abstract in nature, so understanding them requires a great deal of firsthand exploration and sensemaking. Students spend the majority of the unit investigating how sounds travel from a mother dolphin to her calf. These activities provide students with the experience and support to understand a scientific phenomenon that is difficult to observe.

Understanding how humans use patterns to communicate is essential for understanding how digital devices send and receive messages, a topic particularly relevant to many students’ everyday experiences. Using the Code Communicator Tool—an app that allows students to send and receive messages in binary code—students design a way to send a message across the classroom, and compare their method to how digital devices send and receive information across distances. The last chapter of the unit provides the opportunity for students to begin to develop an understanding of the role of technology in communication.

How?

In Chapter 1, students consider the question How does a mother dolphin communicate with her calf across a distance? They begin by exploring physical models of waves made with a rope and a spring toy, and they read about tsunami waves in Warning: Tsunami! Students then observe what happens to the particles in a material when sound travels through it, using the Sound Waves Simulation. As students come to understand that sound energy travels as a wave from a source to a listener, they create a Sound Diagram showing how sound travels through water from a mother dolphin to her calf. Students revise these Sound Diagrams throughout the unit to show their developing understanding of sound waves. At the end of the chapter, the class reviews the ideas from Chapter 1 and incorporates them into an initial scientific explanation of how a mother dolphin uses sound to communicate with her calf across a distance.

In Chapter 2, students investigate the question How does sound energy travel through water from a mother dolphin to her calf? Students come to understand that sound can travel through different kinds of materials and that materials are made of particles that are too small to see by engaging in a variety of multimodal experiences. Students do firsthand investigations of sound traveling from a source to a listener, they gather information about how various animals communicate from the book Sound on the Move, and they observe sound waves in the Sound Waves Simulation. Throughout their investigations, students learn to use the sense-making strategy of visualizing to understand what the various models and visual representations they work with represent. Students then investigate the idea that sound travels as a series of collisions between particles. Students revise their Sound Diagrams to show that when particles collide they transfer energy, and that changes how they move. Students then write a scientific explanation of how sound energy travels through water from a mother dolphin to her calf.

In Chapter 3, students investigate the question How does a dolphin calf know which call is his mother’s call? Students use the Sound Waves Simulation to generate waveforms for various sounds and to create custom sounds that vary in volume and pitch. Through working with the Sound Waves Simulation and reading background information about sound waves in the unit’s reference book, Patterns in Communication, students figure out that the larger the amplitude, or height of a wave, the louder the sound is. They then relate this idea to how dolphins hear one another’s calls. Students also figure out that the wavelength of a sound wave is related to the pitch of the sound, and learn by reading The Scientist Who Cracked the Dolphin Code that each dolphin has a signature whistle that has a unique pattern of changes in pitch. Students listen to real dolphin calls and then use visual representations of the sounds’ waveforms to replicate the sound in the Sound Waves Simulation. Chapter 3 ends with students discussing and then writing a scientific explanation of how a mother dolphin’s call gets to her calf, and how the calf knows which call is his mother’s call. In addition, students see the applications of the scientific knowledge they are learning as they read about different professionals that visualize sound in the book Seeing Sound.

In Chapter 4, students transition from thinking about patterns in dolphin communication to considering the role of patterns in human communication. They investigate the question How can humans use patterns to communicate? by engaging in an activity that challenges them to send an image to a partner by only describing it, which prompts them to consider the difficulties involved in transmitting information across distances accurately. Students read about various communication methods humans have relied on throughout history in Patterns in Communication. They work in groups to devise a method for sending an image across the classroom, using the Code Communicator Tool—an app that allows students to encode and decode messages, using binary code. After students send and receive the messages, they reflect on how accurate the transfer of information was, and why they think so. Through this investigation, students begin to develop an understanding of how digital devices encode and decode information and how humans have devised various methods to accomplish the challenging task of communicating across distances.See less about unit overview