Electric Current Through Students

My grandson's science teacher (5th grade) had a group of students stand in a semicircle. He attached leads from a variable voltage controller to the end students and increased the voltage until they "felt" it. The student in the middle was told to let go to demonstrate a complete circuit. Is this dangerous?
- `Joe (age 69)
Shiloh, Israel

It certainly sounds dangerous to me. It's not that anyone would be hurt if everything goes as planned. It's that things don't always go as planned. 

By the time the voltage was high enough to give a noticeable current through the chain of students, it was likely to be large enough to give a fatal current if it was across a single kid or maybe even two kids. So the teacher was counting on nobody impulsively reaching across and grabbing anything. What if somebody didn't like the tingle on his hand, dropped the wire, and the wrong person picked it up, or it touched some metal surface that somebody else was touching, etc.? 

Mike W.

(published on 01/07/2014)