Jumping in here with relevant experience - because you're absolutely right.
In 8th grade (~16 years ago) my substitute biology teacher organised a "Water drinking competition" poised to elevate our understanding of stomach capacity, etc.
Two of us went to hospital, and ~5 (including myself) had to take multiple days off of school and recover.
It's very dangerous. He lost his job.
What was exactly his thinking here? Do biology teachers study biology because that’s kind of the first things you learn (saline concentration, kidney, etc…)
There was a lady who died from the same thing:
https://abcnews.com/GMA/jury-rules-radio-station-jennifer-st...