Stereo Hangers

Submitting Organization: Community Resources for Science

Grade Level: 1st Grade

Subject Area:  Science  

Standards Alignment: Next Generation Science Standards

Physical Science: 1. Waves: Light and Sound 1-PS4-1. Plan and conduct investigations to provide evidence that vibrating materials can make sound and that sound can make materials vibrate.

Description of the Activity: Can we make sound with a string? Provide pairs of students with a hanger with 1 piece of string tied to each end, and 3 test objects (metal, wood, plastic). One partner holds the strings, allowing the hanger to dangle upside down, with one string close to each ear. The other partner taps the hanger gently with one test item. What does the person holding the strings observe? Do they hear anything? Tap the hanger with a second object, then the third. Does it change with different items? Partners can alternate roles with each item, or after trying all three. Can they explain what they heard?

Discussion Questions:

  • What did you observe?
  • What did you hear?
  • What did you feel?
  • How do you think this is possible?
  • Students may explain that sounds were caused by the string moving; the teacher may introduce the vocabulary word “vibration”. How did the vibration happen, and what did it cause? Can we change the sound we hear by changing our actions
  • Invite students to experiment. What if you tapped the meal hanger with your finger? Or a plastic spoon? Students should come away understanding that vibrations are created by tapping on the hanger, and that different vibrations make different sounds.

Resources Needed: Students work in pairs. Each pair of students needs:

  • One wire coat hanger with two pieces of string (6 inches long) attached to each end of the hanger (nylon kite string works well)
  • A metal spoon, a plastic spoon, a pencil or pen

Link to further resources:

http://www.crscience.org/lessonplans/NGSS/1_HearAllAboutIt.pdf