1

Sound on a String 

Center Activity 

Grade Level: K-2 

Suggested Time: 90 minutes 

10 minutes - Introduction 

5 minutes – Demonstrate building string cup phone 

15 minutes – Rotation 1 

15 minutes – Rotation 2 

15 minutes – Rotation 3 

15 minutes – Rotation 4 

15 minutes – Class discussion of fndings 

Lesson Overview: In this activity, students will rotate through 

a series of center activities to develop a hypothesis for how 

sound travels as they experiment with different types of string, 

sizes of string, types of cups and sizes of cups to determine the 

best method to transmit sound on a ‘string cup phone’. 

Objectives: 

Following this activity, students will be able to: 

• Explain how sound travels. 

• Demonstrate how the transmission of sound 

waves is affected by different materials. 

Materials: 

 Multiple types of string: 2m each 

 Multiple lengths of one type of string 

(examples: 2m, 5m, and 10m) 

 Multiple pairs of various types of cups 

 Pairs of various sizes of one type of cup 

 Nail or screw for the teacher to punch 

holes in the cups 

 Photocopies of Inquiry Activity Sheet 

(or create one age appropriate for your 

students) 

 Large plastic baggies for grouping 

materials at centers (optional for student 

assembly) 

 Chart paper 

 Crayons 

 Pencils 

Next Generation Science Standards (NGSS): 

1-PS4-1. Waves and Their Applications in Technologies for 

Information Transfer: Plan and conduct investigations to provide evidence 

that vibrating materials can make sound and that sound can make materials 

vibrate. 

1-PS4-4. Waves and Their Applications in Technologies for 

Information Transfer: Use tools and materials to design and build a device 

that uses light or sound to solve the problem of communicating over a 

distance. 

Common Core Standards for Mathematics 

(CCSS): 

CCSS.MATH.CONTENT.1.MD.C.4. Represent and 

interpret data: Organize, represent, and interpret data with up to three 

categories: ask and answer questions about the total number of data points, 

how many in each category, and how many more or less are in one category 

than in another. 

Procedure: At each center students will test one variable 

and document their fndings on the Sound on a String 

Inquiry Activity Sheet. Following the activity, the teacher 

will facilitate a classroom discussion by combining the 

individual fndings on large chart paper. This will create 

a class graph for each variable and allow discussion for 

any similarities or differences as the class comes to the 

conclusion of how sound travels. 

For younger students, it is recommended to have the 

various string cup phones pre-prepared at each station. For 

older students, the teacher may demonstrate construction 

of the phones prior to the rotations. For all students, it is 

recommended the teacher models the proper use of a 

string cup phone prior to starting the center rotations. The 

teacher may demonstrate that the string must be pulled 

tightly in order for the vibration to travel through it, remind 

students they should whisper into the phone to allow 

everybody to hear their own partner, and allow time for 

students to practice soft talking with their partner before 

the rotations begin. 

Center Rotations 

Center 1: Students will observe the differences due to string 

material. 

Center 2: Students will observe the differences due to string 

length. 

Center 3: Students will observe the differences due to cup material. 

Center 4: Students will observe the differences due to cup size. 

NGS: Sound on a String: Center Activity http://www.nasa.gov/stem/ccp 
2

Sound on a String Activity (continued) 

Student Procedure for Constructing String Cup Phones: 

1. Thread string up through the hole in the bottom of cup. 

2. Tie a knot on the end of the string inside the cup. If needed, add a paper clip or button to help keep the string 

from pulling through the hole. You may need to tie several knots on the end to make the knot large enough to 

prevent the string from slipping out of the hole. 

3. Repeat steps 1 and 2 with the second cup. 

4. Stand far enough apart so the string is pulled tightly and whisper into the cup while your partner places his or her 

ear near the opening of the other cup. 

5. Rotate through each station and record your results on the Inquiry Activity Sheet. 

Final Discussion: 

Use the class chart to guide the following discussion questions and stimulate interest in further investigation. 

• What is sound? 

• How does sound get from one place to another? 

• Why is vibration important? 

• How do we make sound? 

• How do we hear sound? 

Assessment: 

• For older students: Collect and review completed Sound on a String Inquiry Activity Sheets. 

• For younger students: Ask students to illustrate what they observe at the different center rotations 

• Informal Assessment: Discuss how the materials affected the sound and ask which combination of materials may 

create the “best” string cup phone. 

Extensions: 

• Give each student the opportunity to create the optimal string cup phone by selecting a string material, string 

length, cup material, and cup size. Assemble the phone and allow students to take it home to teach their family 

about sound waves. 

• Have students brainstorm ideas to improve the design of the string cup phone using the same or different 

materials. Then have students test their designs. 

• Use the web resources below to research more about sound and fnd additional sound activities such as the 

Shoebox Guitar, Musical Tube, or Super Sound Cone. 

• Team up with a music teacher to let students investigate how different instruments produce sounds. 

Additional Resources: 

Additional Commercial Crew Education Resources: http://www.nasa.gov/stem/ccp 

Musical Tube Activity: www.grc.nasa.gov/WWW/K-12/TRC/Aeronautics/Musical_Tube.html 

Collection of samples from single notes to full orchestra: www.philharmonia.co.uk/thesoundexchange/sound_samples/sample_libraries/ 

Directions for constructing a Super Sound Cone: https://spaceplace.nasa.gov/sound-cone/en/ 

Web sites may provide teachers and students with background information and extensions. Inclusion of a resource does not constitute an 

endorsement, either expressed or implied, by the National Aeronautics and Space Administration. 

NGS: Sound on a String: Center Activity http://www.nasa.gov/stem/ccp 
Inquiry Activity Sheet: 

Sound on a String! 

Student Name: _________________________________ Date:__________ 

Directions: Fill in the blank with the best answer choice from each center. 

Center 1: Type of string 

1. The string made of ____________ made the loudest sound. 

2. The string made of ____________ sounded the clearest. 

Center 2: String Length 

1. The string that was ____________ long made the loudest sound. 

2. The string that was ____________ long sounded the clearest. 

Center 3: Type of cup 

1. The cup made of ____________ made the loudest sound. 

2. The cup made of ____________ sounded the clearest. 

Center 4: Cup Size 

1. The ____________ size cup made the loudest sound. 

2. The ____________ size cup sounded the clearest. 

Draw: Show two students using the materials you think work best together to make sound. 

NGS: Sound on a String: Center Activity http://www.nasa.gov/stem/ccp