https://www.cdc.gov/homeandrecreationalsafety/water-safety/w...
I would guess the trend is not so bad in Queensland. One thing that is very impressive here is the number of pools in schools, including public schools, and the very, very active swim programs that go with them. Brisbane probably has one of the best swimming cultures in the world (backed up by the number of swimmming champions that have come from here).
Watching my nephews that nature of their swimming seems to be a bit different, for me we were riding or bikes to pools/beaches by ourselves from the age of about 9, they live in Brisbanes suburbia and have to be driven to a pool/beach and then supervised. They're largely left to their own merits once they get there, but it's more of a family thing than a friends thing and they don't have to learn there own dispute resolution and the like, nor do they get to decide when to go and when to leave.
You may debate how useful they are, or if the frequency of school shootings is sufficient to justify them, but I will point out that the number of times I have had to evacuate a school (admittedly, due to a bomb threat) is equal to the number of times we had to "assume the position" for a tornado threat (exactly once).
Note that three of these are in the top 10 (and 2 in the top 5) if you rank them by deaths.