School cap of Helena Czarniecka’s State Secondary School for Girls with a monogram

A school four-cornered hat, commonly known as a cap, was an indispensable part of the school outfit. School uniforms have existed in Poland for a long time. At the beginning of the twentieth century, girls' school outfits consisted of navy-blue blouses with white collars and half-calf long pleated skirts. Additionally, girls wore hats. The boys' costumes were similar to military uniforms, with a stiff, starchy white collar.

In the interwar period, the appearance of the school uniform was regulated by the school’s rules. The girls' outfit often was a skirt with folds, a blouse of the same material with cuffs and piping, and a white collar.

In the very famous Union of Lublin Female High School, the uniform was a buttoned dress with long sleeves, a belt, pockets and a white collar. The stockings had to be dark. The out-of-school dress was also regulated; schoolgirls were exempt from the dress code only during summer holidays. The Jędrzejewicz reform (1932-1933) introduced the obligation to wear a badge, each grammar school and high school having its own pattern.

After the Second World War, the most characteristic attributes of schoolgirls’ outfits were knee-length navy blue aprons with white collars, navy blue coats and berets. Boys wore dark blue suits. The dress code was obligatory for the whole school year, not only at school, and it was only lifted during the summer holidays.

During the communist period, aprons were worn, sewn from black satin fabric similar to a pillowcase, later from synthetic fibres, usually navy blue, sometimes maroon. A boy's apron resembled a pilot's jacket with two breast pockets, while a girl's jacket was longer and belted at the waist. The shared element was a white collar with buttons. In some primary schools, aprons were worn until the end of the 1980s.

The idea of reactivating the uniform was revived in 2006, and it was abolished in 2008, leaving the issue to school principals.