And to think that i used to climb phone poles with battery clamps and a volt meter so we could get a band to play on a hay wagon in a field....
When I was a kid, there was a “young adult” science project book in the grade/middle school library. The projects were absolutely, seriously dangerous. Some of them I remember (or DID), for example:
1. Make a “salt-water rheostat” using direct line current for other experiments (!)
2. Using (1), make a carbon-arc lamp using the carbon rods from old-fashioned carbon-zinc batteries (!!)
I seriously wonder if that book still exists in there...the library and school do.
When I was in high school, I made a rather high-powered carbon-dioxide infrared laser, that was so dangerous I took it apart in 1/2 hour and would not let my friends rebuild it. It was based on a Scientific American article (back when Scientific American was scientific, and The Amateur Scientist was a scientist). That thing wouldn’t just take your eye out, it would catch the back of your head on fire. And it was invisible!
“Don’t try this at home”
These kids need a mentor or classes to apply their enthusiasm more safely. Note the more safely part, as working on high voltage DC or AC requires a buddy system just as in professional diving.
A Jacob’s Ladder needs enough voltage to carry an arc with several inches of separation before re-striking lower upon the “V” formed by the conductors. It will happily jump through a person to reach grounding through concrete.
More than likely he played with the electrical socket and stopped is heart.
Have to watch your kids.