Teaching kids at the National Museum of Nature and Science


Me holding up a couple of vocal tract models.

Last weekend, our lab gave a demo at the National Museum of Nature and Science here in Tokyo. They were running an event called Science Square, where kids can come and meet scientists and engineers and participate in hands-on activities. If you’ve never been to the museum, it’s a really cool place, right inside Ueno Park. They’ve got dinosaurs!

We didn’t present anything about plesiosaurs, though. Our lab gave a demo aimed at elementary school students on how human speech works. More than 300 kids walked through, and got to make their own recordings, play with the equipment, and get a print out of their own voice. We had a few curious adults come through as well. Naturally, I was tasked with explaining things to foreign visitors, but honestly anyone in our lab has good enough English to do that. Mostly, I explained the basic theory, helped the kids make recordings, and used my experience as an Eikaiwa clown to amuse the little ones.


Five models, one for each of the Japanese vowel sounds, plus a small black electrolarynx for producing vibrations.

Rei Uchida (2nd-year PhD student at Arai lab) models a model.

Rei Uchida (2nd-year PhD student at Arai lab) models a model.

First, we gave them a short explanation of the Source Filter Theory—although obviously we didn’t call it that! We had the kids say “ah” while touching their throat to confirm that their vocal folds are vibrating. “It goes buru-buru, doesn’t it?” Then we talked about how the shape of the mouth changes the sound, and used plastic tubes to show how that works. I’ve posted about the tubes previously, so check out that video if you want to see and hear how they work.

These models that Professor Arai made are super popular. Experts love them, students love them, even people who know absolutely nothing about phonetics think they’re pretty cool. Geeky explanation here.

Mee Sonu, a recent graduate from Arai lab, showing some kids a spectrogram.

Mee Sonu (Arai lab graduate and assistant professor at Nihon University), showing some kids a spectrogram.

After that, the kids did a little matching game. We had them say “aiaiaia”, “asasasa” and “itatata” into a microphone, and they got to watch a spectrogram of their voice up on a screen. We explained a little about how the sounds work, really simple stuff like “the t makes a white space, because for a very short time there’s no sound”. Then they did a matching game, and drew lines to connect each phrase to the matching spectrogram. That’s right, we taught six year olds how to read a spectrogram! They were pretty good at it, too.

Eri Iwagami (PhD student) chats with a little girl, while Yuri Amimoto (Master's student) edits the image of another kid's voice.

Eri Iwagami (PhD 1st year) chats with a little girl, while Yuri Amimoto (Master’s student) edits the image of another kid’s voice.

From there, we recorded them saying their name, and printed the spectrogram out on a little card. This part was by far the most time-consuming, so there was always a little crowd of kids piled up, waiting for the lab members to copy, paste, crop, zoom, and edit the spectrograms into a little template. I was really impressed with my fellow lab members, though—they were very good at chatting with the kids and making them feel comfortable.

Hirayama-kun plays back a girl's voice using a spectrogram reading program.

Hirayama-kun plays back a girl’s voice using a spectrogram reading program.

The last step was pretty dang cool. The kids took the printout of their voice and put it under a camera. Using a special spectrogram reading program, the computer played back their voice. Not perfectly, mind you; it sounded pretty robotic, since there’s no pitch information, and the details get fuzzed out a bit. The neat thing about the program, though, is that it will translate any red line on the spectrogram into a pitch contour. The kids got to bend a piece of red wire and lay it on the card, and listen as the program played their own voice with whatever intonation they wanted. Neat!

I really just did the first two parts and explained things to parents and foreign visitors, so I didn’t have much of a hand in planning or organizing the event. All the credit for that goes to Ayaka Nakajima, a second-year Master’s student. She planned it all, made the worksheets, and even drew the cute little characters. She’s a superstar!


Ayaka Nakajima (Master’s student) shows off her awesome worksheet.


English teacher, student of Japanese, and aspiring linguist.

Tagged with: , , , ,
Posted in Phonetics and Phonology
2 comments on “Teaching kids at the National Museum of Nature and Science
  1. It is pretty cool that these types of things are available for kids to learn about. It is funny that you mentioned that a few curious adults came along too. This makes me wonder why there are not nearly as many learning opportunities for adults, I wish there were more. Could you tell me more about how the electrolarynx works?

    • gengojeff says:

      Sure! It’s actually a fairly simple device, but there are more advanced versions.

      When we speak, we push air from our lungs, through the vocal folds, and out through the mouth and nose. Lungs are the source of air, while the vocal folds provide a vibration that adds power to the sound. When you whisper, the vocal folds are apart, but when you speak normally—we call this “modal voice”—they flap against each other rapidly. Men’s vocal folds vibrate somewhere between 60 and 200 times per second, while women are usually between 150 and 300.

      People who have had a laryngectomy don’t have their vocal folds anymore, so the electrolarynx simply provides that vibration for them. They can hold it up to their throats, and it vibrates to add energy to the voice that the vocal folds would usually provide. Basic models just run at a single, constant buzz, but you can get them with a slider that lets you adjust the vibrations up and down in frequency, allowing you to have ups and downs in your intonation as well.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

  • RT @JordanUhl: At Trump’s rally last night: -He endorsed a pedophile -A speaker compared his Israel decision to “Jesus’ return” -He mock… 4 days ago
  • RT @aomuro: 朝の流れ https://t.co/zaJelikU7M 1 week ago
  • RT @ClickHole: A Second Chance: This Amazing Organization Helps Disgraced Pedophiles Rebuild Their Lives By Getting Them Elected To Politic… 1 week ago
  • RT @profwolff: Old people, living in cars or vans, are Amazon employees. Their labor helps make Bezos the richest man alive. His company ge… 1 week ago
  • RT @profwolff: Workers, the young, women, students, minorities – all savaged by GOP tax bill. Yet the Democratic Party doesn't mobilize in… 1 week ago
%d bloggers like this: