The following document is from the Appendix of a book, Suttering: Science, Therapy and Practice by Tom Kehoe.

High School Stuttering Science Experiments

The following experiments were developed for a science museum workshop teaching science to children who stutter. The experiments could also be used as high school class projects.

Before you start an experiment, develop a hypothesis that you will test. Afterwards, present a theory explaining your results.


1) Interview a successful adult who stutters. This could be an accountant, a lawyer, or a teacher. You can find such a person by calling your local National Stuttering Project chapter. Call the National Stuttering Project at (800) 364-1677 to find your local chapter leader. Ask the following questions:

How did stuttering affect your childhood or high school years?

How has stuttering affected your adult life?

How has stuttering affected your choice of career?

How has stuttering affected your relationships or marriage?

What stuttering therapy have you had? Did it help you?

How severely did you stutter when you were younger?

How severely do you stutter now?

Are there situations in which you stutter more, or stutter less?

Are there are speaking situations you fear or avoid because you stutter?

What do you think causes stuttering?

2) Attend a meeting of your local National Stuttering Project chapter. Write a report about what topics were covered and what people said about stuttering. Call the National Stuttering Project at (800) 364-1677 to find a self-help group in your area.

3) Help your speech pathologist organize a "Youth Day" weekend stuttering workshop for children and teenagers who stutter in your area. The National Stuttering Project has a book explaining how to organize a "Youth Day" workshop. Call the National Stuttering Project at (800) 364-1677 for the book.

4) Interview your speech pathologist about stuttering. Or find a speech pathologist who specializes in stuttering. Your school district may have such a specialist. Or you can call the Stuttering Foundation of America at (800) 992-9392 to find a stuttering specialist.

Ask the following questions:

What causes young children to stutter?

What causes stuttering in teenagers and adults?

What are two treatments for stuttering? How are they different? Describe the techniques and goals of each therapy.

Why do more boys stutter than girls?

What other speech disorders do children and teenagers have? How are these speech disorders different from stuttering? How are the treatments different?

Why did you choose a career in speech pathology?

5) Read a book about stuttering and write a book report. Ask your speech pathologist to recommend a book.

6) Write a report about a famous person who stutters. For example, you could write a book report on James Earl Jones' autobiography.

7) For history class, write a book report on Stuttering: The Search for a Cause and Cure, by Oliver Bloodstein, Ph.D. (published by Allyn & Bacon, about $50).

8) Observe a speech pathologist treating a preschool child who stutters. Write a report about this, answering these questions: What games did the speech pathologist play with the child? What was the purpose of the game? What did the speech pathologist talk about with the child's parents? What did the speech pathologist learn from the parents? What did the parents learn from the speech pathologist?

9) Find out if any of your relatives stutter. Draw a family tree showing your relationship to the person. Present evidence that stuttering has a genetic cause, and evidence that stuttering is not genetic.

10) Does another student in your school have a disability? This could be a physical disability, such as a hearing loss, or a mental disability, such as dyslexia. Compare stuttering to the other student's disability. Are different life activities affected? Which disability is more challenging to live with? Has the other student always had the other disability, or has it developed recently? What is the treatment for the other disability?


Make an audio or video recording of a person who stutters. Make a tape of a person who doesn't stutter.

11) What kinds of disfluencies does the stutterer have? These might be blocked airflow, repeated sounds or syllables, or prolonged sounds.

What kind of disfluencies does the nonstutterer have? These might be interjections such as "um," "uh" and "you know"; changing what he or she says in the middle of a sentence; repeating words or sentences; pauses in the middle of a sentence; misarticulations, such as not being able to say the /r/ or /w/ sounds properly.

Count the number of disfluencies in a 100-word section of the tape, for the stutterer and the non-stutterer. Compare the disfluency rates of the stutterer and the nonstutterer.

12) Count the number of words or syllables each person says in a three-minute section of tape. Compare the speaking rates of the stutterer and the nonstutterer. Does the stutterer talk faster or slower than the nonstutterer? Are parts of the stutterer's speech too fast, and other parts too slow?

13) Ask each person if there are speaking situations he or she is afraid of, or avoids. Are there people each doesn't like to talk to? What about speaking to a group of people?

14) Repeat some of Wendall Johnson's 1937 studies of adaptation and anticipation (see section on conditions that increase or decrease stuttering).


15) Build your own delayed auditory feedback (DAF) device. Use a Dolby Pro Logic surround-sound home theater amplifier, or an electric guitar effects processor, or an electric guitar delay pedal, or a reverb control. You'll need a microphone, amplifier, and headphones.

16) Build your own frequency-altered auditory feedback (FAF) device. You could:

Use an electric guitar effects processor, microphone, headphones, and amplifier.

Use a "Voice Changer" toy. These look like plastic megaphones, and make your voice sound like an alien or a robot, and cost about $20. You will have to wire out the speaker, and wire in headphones. Use headphones with built-in volume controls, or add your own volume control. Use a Radio Shack 1-megaohm potentiometer ($1.29, 271-211). Solder the two outer pins to the two speaker wires. Solder the headphones jack to the middle potentiometer pin, and the ground (black) speaker wire (this should ultimately connect to the battery's negative terminal). Use Radio Shack's switching jack ($1.39, 274-246) so that the speaker switches on when you unplug the headphones.

17) Build your own masking auditory feedback (MAF) device. You could:

Use a frequency generator. Your electronics teacher may have one. Set it to generate a 125-Hz sine wave.

JDR Microdevices (800/538-5000) has an "Op-Amp Function Generator" kit for $8.95. You'll need to add an amplifer and headphones.

18) Go to a hardware store and buy a short piece of hose (about twenty-five cents). Hold one end to one ear, and speak into the other end. (Or you put a Fisher-Price toy plastic stethoscope in your ears, and talk into it. This works better because you hear with both ears.)

19) Test the effectiveness of the above four devices on the speech of a stutterer. See if the devices alter the speech of non-stuttererers.

20) Find a speech clinic that has a speech biofeedback system. Try it out and write a report about what the biofeedback system does.

added with permission, January 15, 1997