I call it their plastic educator.
4 seconds sound clip from the Forbidden Planet (1956) movie soundboard.
You can hear this line at 00:54:14 in the Blu-ray version of the movie.
Quote context
[...]
- A thing like this, it's... it's too big to evaluate.
- Think what a discovery of this kind...
- Dr. Morbius what is this device over here?
- I call it their plastic educator.
- I often play with it myself for relaxation.
- Although working here, I sometimes wish I'd been blessed with multiple arms and legs.
- Now, you can see that this headset was designed for something much bulkier than my human cranium.
[...]