Butterick patterns for girls. December 1924, Delineator.
An entire page of patterns for girls and young teens had a Christmas theme in 1924. Above, left, a very young girl holds mistletoe over her own head. Right, a little girl is ready for snow in her red hat, coat and leggings. (Imagine buttoning those leggings onto a squirming 3 year old!)
Holiday dresses for girls, December 1924. The older girl’s hem is just below her knees, while the younger girl’s hem is mid-knee.
Dresses for Girls 8 to 15, 1924; Woman’s dress, 1928
I’m always struck by how “right” the proportions on early Twenties’ dresses for girls look, while the length of dresses for women and older teens was still quite long:
Patterns for grown women (“Ladies,” bust size 32 to 44 inches.) September 1924. Delineator.
Dresses for misses aged 15 to 20, November 1924. Not a rouged knee in sight — yet.
Patterns for girls under 15, October 1924. Knee-length!
Before the late nineteen twenties, as girls got older they dressed more like grown women, exchanging short skirts for longer hems.
The younger the girl, the shorter the dress in 1924.
Those hems make even these 1924 party dresses for older teens look long and dowdy.
These teens are wearing quite long hems, compared to their younger sisters. December, 1924.
But, by 1927, adult women were wearing dresses as short as the pre-teens of 1924! Women aspired to look younger, and youth set the fashions.
Left a teen under 15, 1924. Right, a grown woman from 1927. Both are Butterick patterns illustrated in Delineator.
In 1927, these sophisticated women are wearing hems that only schoolgirls would have worn just three years earlier.
Ladies’ fashions from November 1927 are as short as this girl’s dress from 1924.
This is just a sample of the “youth” trend of the late Twenties. Of course, by 1927, young teens were showing the entire knee….
Coat and dress for 15-and-unders. November 1927.
For girls 12 to 16 years of age. November 1927.
As one (hair dye) advertisement put it, “You Cannot Afford to be Gray because … this is the Age of Youth.” (1925.) Happy 2020!
witness2fashion 
Fascinating how quick the change was, and how our perceptions of twenties fashion are actually based on just a few years.