The film you are referring to is a Belgian documentary titled Sexuele Voorlichting
The film explores themes such as body development, sexual hygiene, masturbation, menstruation, and the mechanics of sex and childbirth. The film you are referring to is a
The "work" mentioned in historical archives from 1991 often refers to the audio-visual (AV) revolution in classrooms. This was the golden age of the "educational video." The film you are referring to is a
3.1 Puberty timing and variation