@heartofberries UK and I think my experience of PE class is echoes what others from the UK have said. Was in high school between 2007-2013 and PE was mandatory for the first 5 years regardless of whether you chose PE as a subject for GCSE level (Year 10-11).
In year 7 we did the bleep test which was awful and humiliating depending on how early you were out. We were a co-ed school but PE was done separately for boys and girls. I can't account for whether there was a big difference in what we were taught but I definitely never played football and I doubt the boys ever played netball.
I remember very early on there was a clear divide between the girls who were good at sport, who were on the school football and netball teams and actually enjoyed sports day versus the rest of us. The teachers always favoured these girls and unlike other subjects, there was no concept of improving or moving for your health or because it felt good. It definitely felt like you were either naturally good or not. We also had something called 'sports scholars' in my school who had special kits and did extra curricular activities. They were also invited after school when our new sports hall was opened by Dame Jessica Ennis!
In terms of what we actually learnt, there was a huge variety of sports - I remember hockey, rounders, netball, dance, trampolining (that was a fun term!). I remember doing circuit training once which included sit ups. Usually we would pick a sport and learn it over a term. I remember it being fairly dull as we'd spend ages learning technique and hardly any time playing. If our teachers weren't around and we had to have a cover lesson, that's when we would sit in a classroom and learn about muscles and physiology. We did athletics leading up to sports day which included pole vault, javelin, shot-put, hurdles, sprinting, long-distance running. Everyone had to take part in at least one event on sports day.
GCSE level is where more standardisation comes in as teens have chosen to do that subject for a certificate in Year 10-11. GCSE students learnt the fitness and science aspect of PE (I think, I didn't do it so please shout if I'm wrong!). Non-GCSE students had to still do PE once a week due to government guidelines. This was the best experience I had of PE in high school because all of the girls who were keen at sports had been filtered out to the GCSE class and the teachers didn't care that much about us/didn't have to teach us so we just got to play whatever sport we wanted. At A-Level (Year 12-13) if you wanted to continue from GCSE, there would be more of the science aspect and there were no mandatory classes for anyone not actively studying PE as a subject.
Overall, I wasn't particularly good at PE and I am so mad that there wasn't more of an emphasis on learning how to be fit to be healthy rather than arbitrarily being good at sports. In the UK over half of girls stop doing sports as teenagers. We even had a huge
campaign a few years ago to encourage women and girls to exercise. It was actually really cool cause it showed women of all ages, shapes and sizes doing a variety of sports. So no, I don't think we're a particularly good example of teaching fitness.