And it's all
serai1's fault. She posted a couple of videos
here and then figured out that the children were chanting "Pythagoras Switch". Then I searched the term at YouTube and found lots more gadgets. They're curiously soothing to watch.
Of course, having watched a bunch of gadgets I decided to click on the
Algorithm March... The ninjas are a nice touch.
And then there's
this.
*wanders off singing Japanese badly*
ETA: It appears to be a generic Youtube addiction. Found some
Dave Allen too.
And
another funny video. This one is
elendiari's fault.