My mother, Allegra Knapp Mertz, bought Connecticut Moth #1020 from Skip Etchells in 1947, named her Loon, and frostbited at Larchmont (NY) Yacht Club over the winter on 1947-48. Her husband, Jim Mertz, was a member of American YC in Rye NY, and Loon went there in 1948. She was placed on one of the docks. I was 7 years old at the time and found that I could push her off the dock and go sailing. The only problem was getting her back on the dock at the end of the day. I did this for about 6 weeks before I was caught. Mom came down to the club to go sailing and the sails and boat were missing. Luckily I sailed around the AYC main dock and made a perfect landing, wouldn't have broken an egg, as she said. Looking back, it was probably a bit crazy for a 7 year old to sail around Milton Harbor, and a bit beyond, unsupervised, but that was then. I loved that boat and think it is the reason I am still racing small boats, currently a Lightning, at age 70 with my wife Susie as forward crew. There is a half model of her (Loon) in the American Yacht Club.Jamie (age 4) also faintly remembers his Mom and step-dad fishing a large log onto the Mothboat to use later as firewood.
For a tribute to Allegra Knapp Mertz, here is a link to her obituary in the New York Times.
I've talked to a fair number of my generation and many learned by sailing on their own; not so much through organized instruction; just going out and going sailing.