I think it was when I was 13 but it was more in a scientific way. It's weird for me that in countries like the US they speak about abstinence because in France we never talk about it in class, it isn't even considered as a means of birth control.
I remember when in class we had to list the different means for birth control and someone, as a joke, said abstinence and the teacher said "oh no! you're crazy!". lol