I taught my child how to blow bubbles in the water.
Since I'm taking baths with her now, I figured, I might as well show her a thing or two.
We tried in swim classes but let's be honest, swim classes at 6 months of age is for Mom to get out and try to socialize and feel like she's doing something beneficial for her child. Meanwhile at 6 months old, if you are feeding/nursing, changing diapers and providing some stimulation via reading and occasional walks, you are doing fine.
In swim classes at 6 months, the most advanced thing she did was sit on the edge of the pool and flop into my arms. I say flop because a 6 month old can't jump. They sort of sit there teetering and then plop into your arms.
So now my kid likes to 'hold her nose, breathe and blow bubbles.' I've seen her 'teach' her walrus and sea horse.
It's the physician way of learning, see, do, show.