[Sidenote: Periods of early life.]
In Sec. 8 of the Report of the Committee of Three of the American
Federation for Sex-hygiene, by Morrow and others, the life of the child
was divided into four periods, namely,--under six years, from six to
twelve, twelve to sixteen, sixteen to maturity. This division now seems
to me to be too arbitrary, and I have come to believe that it is more
helpful to consider sex-instruction for three periods as follows:
pre-adolescence (ending at eleven to fourteen years); early adolescence
(twelve to sixteen years for girls, thirteen to seventeen for boys);
later adolescence (sixteen to twenty-one for girls, eighteen to
twenty-five for boys).