Puberty has been around far longer than have sex-ed classes. Those yearnings were controlled in the fifties and early sixties, but they burst out of bounds afterwards.
One could conclude from increased problems since the 70s that the sex-ed classes weren't very helpful. One could also conclude that however it was managed prior to that had been more effective.
African-American illegitimacy rates in 1960 were 23.6%. This was in a largely religious community, with very low rates of completing high-school; hard to blame it on public schools.