Gosh, the gym strip... we had heavy cotton rompers with elastics around the legs. I was thin and the elastic would bite into my thighs. Ours were red.
It seems to me the school year was divided into sport seasons; volleyball, basketball, field hockey, etc, to track and field in the early summer. The thing is that I was never really good at team sports because I'm not very physically competitive.
Our children's gym curriculum followed the above, but they included some other sports occasionally, such as tennis and golf. I did hear complaining that the only kids that got good marks in gym were the ones that made the basketball team; our town is basketball crazy. I remember speaking to a gym teacher, that if you learned all the rules of the sport, participated with some enthusiasm and were a good sportsman, then you should get good grades. It can be demoralizing to know you are not the best at something, and kids can be easily put off sport.
Meanwhile as an adult, I love hiking, running (slowly now), skiiing, kayaking, etc. There are plenty of other ways to enjoy being physical without joining teams.