He analysed the language used and used historical sources to conclude it was an early Brecht, according to the Welt am Sonntag newspaper.
He said the piece is a satire, describing in joyful detail how the girls attended their graduation ceremony in white dresses, preparing themselves as mothers of the German people.
The language he uses was even then archaic, and the over-cheerful atmosphere can only be taken as a farce as it sits in direct contrast to the reality of the time – with Germany about to be defeated at the end of World War I.
The girls he wrote about had been sharing their school building with two companies of Bavarian infantry for four years, while the author himself was constantly scared of being conscripted.
Hillesheim said the piece was interesting because it was perhaps the last piece Brecht wrote before making the "quantum leap from self-important little writer to great poet."
But the story was not just about making his mark in the newspaper, Hillesheim said – Brecht also wanted to impress Paula Banholzer, a local girl he was later to marry.