During my whole school career I never wore an uniform. No school had one, apparently just after the war, the Germans had seen uniforms enough and also the parents had no money to spend for uniforms. Even in posh schools uniforms were not allowed, because it would kill the individuality of the child.
The first school uniforms in my life I saw when I moved with my parents to Belgium. I had never seen that in my life, the girls with blue skirts, white blouses and blue cardigans I saw on the street when they came out of school, I found awful. I was usually wearing jeans (which didn't exist in Belgium yet it was 1959) a dress, a skirt or whatever came into my mind. A uniform was in contradiction with the freedom of each child.
Today wearing uniforms in schools is still a big discussion in Germany. There are very few schools who do it, but not with a lot of success.
The black shadow of the past is still hanging over Germany
The minister of education in Germany decided against school uniforms which are after the Second World War, still in fresh memories of the uniforms of the Hitler Youth and the League of German Girls.
The explanation is :
The introduction of a school uniform would mean that students are obliged to wear a uniform at school. That is, they can not decide for themselves what they want to wear and not everyone can wear what suits him and most importantly fits. Thus, the development of individuality is limited and the opportunity to express his personality through clothes would disappear.
And Wikipedia explains :
In recent times, the introduction of school uniforms has been discussed, but usually the expression "uniform" (the word is the same in German) is avoided in favour of terms like "school clothing" ("Schulkleidung"). School clothing has been introduced in a small number of schools, for example in Hamburg-Sinstorf in 2000, and in Friesenheim and Haag (Oberbayern) in 2005. In these cases the clothes are collections of shirts, sweaters, and the like, catering to contemporary fashion senses. Uniforms in a more traditional sense are almost never proposed in earnest.
The Bildungsstreik (education strike) movement fights against School uniforms because they are mentioned being part of some kind of militarism
In other European countries wearing an uniform at school is also most uncommon. Except of course the UK !
In Belgium school uniforms exist less and less, some catholic schools still have uniforms but not the public schools. In total 8 schools in the whole country.

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