I remember learning how to swim.
We held onto the edge of the pool and bobbed our heads up and down into the water and blew bubbles. Just standing still - no leg movement.
Then we used those floaty boards - our teacher would grab onto the other edge, and we would kick our legs so we propelled ourselves forward, and later added putting our heads into the water and blowing bubbles at the same time.
Then once we were good at propelling forward, we started propelling our arms one at a time with the floaty board, (bobbing head, kicking legs) and eventually without the floaty board.
Hey, I never realized it, but they sort of taught us a piece at a time. Those smart instructors!
I really liked having them throw the rings at the bottom of the pool and jumping in to get them. I guess that strengthened our ability to hold our breathes and use our limbs to push to the surface.