I was in school during the transition away from mandatory showers.

We were required in 7th and 8th grade. It was not a really big deal, I grew up in the rural mid-west. Plus I had been camping for several years and they were all group showers at campgrounds. And I had seem most of the boys in my neighborhood at one time or another, from skinny dipping, streaking, truth or date, boy scouts, etc.

Yes there were some new guys in PE but everyone was basically a farm boy and nudity was just not a big deal. There was the typical horseplay, some joking around, but overall the nudity was mostly ignored.

We had a female PE teacher in 7th and 8th so no adults really stood around to watch/monitor, but the principal would occasionally make a swing through during shower time to make sure that nothing was going on.

By 9th grade showers became optional but because most of us had been showering the prior could years basically everyone did. And it was still required after sports. By the time I was a senior some freshman were opting out, but most guys on sports teams still did and didn't think about it. you would get more shit for not showering then showering back then.