Hands-on Activity Echolocation in Action!

Learning Objectives

After this activity, students should be able to:

• Explain the basics of echolocation.
• Explain that engineers developed SONAR based on natural echolocation.

Educational Standards

Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards.

All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standards Network (ASN), a project of D2L (www.achievementstandards.org).

In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc.

NGSS: Next Generation Science Standards - Science

Common Core State Standards - Math

International Technology and Engineering Educators Association - Technology

State Standards

Materials List

Each group needs:

• 1 blindfold
• Clipboard or hardcover book
• 2 pencils
• Variety of crayons
• 2 copies of the Echolocation Worksheet
• 2 copies of the Echolocation Bar Graph Worksheet

Worksheets and Attachments

Pre-Req Knowledge

Definitions of longitudinal and transverse waves (Lesson 1), wavelength and amplitude (Lesson 2), Frequency (Lesson 3), Sound Waves (Lesson 4).

Introduction/Motivation

We have been talking about sound waves and how animals and engineers use sound waves to "see" underwater or in the dark. Who remembers what it is called when animals do this? (Answer: echolocation) That's right — echolocation! Engineers developed a technology based on the natural echolocation that animals use. It works pretty much the same way, but we call it something different. Who remembers what it is called? (Answer: SONAR) Terrific! SONAR is a great example of how engineers can learn from the world around us and use ideas from nature to create new ways to help people.

Today you are going to have a chance to try out echolocation for yourselves. We are going to break up into teams of two. Then, one person wears a blindfold and guesses where the sound is coming from as the other person makes snapping or clapping noises in front of them, behind them or to their side. It is a fun challenge to learn about echolocation. Are you ready to try it out? Let's get started!

Procedure

Background

Sound travels in waves through the air to the ears. Depending on the location and intensity of the sound, the ear can usually locate the direction of the sound.

Animals — such as bats, whales and dolphins — use sound to see by emitting sounds that echo off other objects and then return to their ears. Depending on how long it takes the sound to reach their ears and the direction it comes from, these animals can determine the location of the object.

Engineers have mimicked this natural echolocation in Sonar and Radar, which work basically the same way as echolocation in animals.

In this activity, students will try to determine the location of nine sounds made from various locations in front of, behind or to the side of them. Try to spread students out as much as possible so that each team can focus on their own clapping or snapping noises without being distracted by other teams. Conducting this activity outside or in the school gym is an excellent idea.

Before the Activity

• Copy the attached worksheets (each student needs one Echolocation Bar Graph Worksheet and one Echolocation Worksheet).
• Make enough blindfolds (large bandanas or strips of fabric) so that each group of two students has one blindfold.

With the Students

1. Go over the activity Introduction.
2. Break the students into groups of two.
3. For each team, have one student sit in a chair and the other stand nearby with the Echolocation Worksheet.
4. Have students gently blindfold their partner so that they are unable to see. Remind them not to peek!
5. Have the non-blindfolded student snap or clap their fingers while the other student guesses the location from where the snap came.
6. Students should record their partner's response on the Echolocation Worksheet after each snap/clap.
7. Have students follow the Echolocation Worksheet for all nine snaps or claps, and record all responses on the sheet. Students should put a check mark if their partner guessed correctly and an X if they guessed incorrectly.
8. Ask students to write down the number of times they guessed correctly for each location (side, behind or in front).
9. Have students switch places and repeat the procedures. Once both students have guessed, have them give each other their worksheets, so they can use them to create their own bar graphs.
10. Help students color in their Echolocation Bar Graph Worksheet with the number of times that they guessed correctly for each location.
11. Talk as a class about the results! Discuss why some locations may be harder to guess than others. (Be aware that noise from other teams will likely be a contributing factor to erroneous guesses.)

Assessment

Pre-Activity Assessment

Who Remembers?: Ask students to raise their hands and share one thing they remember from the lesson. Once students have shared, they must leave their hands down.

Activity Embedded Assessment

Teacher Observation: Walk around while students are completing the activity and assist them as needed. Talk with students about how challenging or simple it is to locate the sounds. Remind students that some animals are great at echolocation, and engineers mimic (in Sonar) this natural animal response.

Post-Activity Assessment

Results Analysis: Have several students share their bar graphs (if you have time, you can make one giant bar graph for the entire class). Talk about the results, and discuss why some locations were perhaps harder to guess than others. Encourage students to think about why noise from other teams may have made it harder to guess the location of the snaps or claps.

Investigating Questions

• How does Sonar work? Do a class project to learn more about how engineers developed and use Sonar.
• How does ultrasound work? Research new developments (such as 4D ultrasounds) in imaging technology for ultrasounds.

Safety Issues

To ensure groups do not trip over and bump into one another, conduct this activity in an area with plenty of space.

Remind students to stay seated while blindfolded.

Troubleshooting Tips

Some students may not feel comfortable being blindfolded; if this is the case, allow them to complete the experiment with their eyes closed.

Activity Extensions

In a quiet place with few obstructions to trip over, allow the students to wear a blindfold (or close their eyes) and try walking around. They can try making noises, like clicking, or snapping their fingers. See if they can tell when they are close to a wall, another person, or a door. Several non-blindfolded students and/or adults should monitor the group to ensure no accidents occur.

Activity Scaling

For upper grades, have students analyze the data using a graphing tool like Excel®. Students can plot actual location of the snap versus real location and then find the percent of correct responses.

For lower grades, the activity should still be appropriate, although students may need more support and guidance.

References

Copyright

Contributors

Supporting Program

Acknowledgements

The contents of this digital library curriculum were developed under a grant from the Fund for the Improvement of Postsecondary Education (FIPSE), U.S. Department of Education, and National Science Foundation GK-12 grant no 0338326. However, these contents do not necessarily represent the policies of the Department of Education or National Science Foundation, and you should not assume endorsement by the federal government.