The theory of gym class is that it should teach you how to be healthy and fit, and teach you the basics of a couple different activities that you can do to get and stay healthy and fit, in the hopes that at least one of them will be something you enjoy doing enough to do it outside of gym class.
The practice of gym class is that a former jock who doesn’t understand why anybody wouldn’t live, eat, sleep, and breathe sports gets to divide a bunch of kids into teams and play team sports; the jocks on the teams play well, and nobody else cares, and everyone resents it.
I’m in favor of mandatory gym class that resembles the former. Not so much in favor of the latter.
My high school gym class had a unit on volleyball each year. I hated it; it was misery. We spent 20 minutes practicing bumps and sets and spikes and serves, and then 20 minutes playing. The more athletic people would get into it, and yell at the less athletic/more apathetic people who were, in their eyes, preventing the team from winning. It was never over fast enough. Then I got to college, and my fraternity had a volleyball net on the quad, and I spent hours playing, and having a blast.
And in my late 20s I decided to get in shape and joined a gym, and was amazed at how relaxing and meditative working out could be. I wish I had learned that at 14.