A lot of times, within hundreds of anime series, we’ve seen high school girls wear super short skirts that would be impossible to see in real life because they would easily expose their underwear. Obviously, this does not happen in the anime series because gravity works in a “different” way, in the same way that Goku’s hair never gets ruffled.

Anyway, jokes aside. It is not that the schools deliver the uniforms with skirts this short, but that the girls themselves pick up the skirt and they use a belt to keep it at the height they want. This process consists in that, already with the skirt on, they begin to make a hem from the top, which makes the skirt begin to get shorter and shorter. When it reaches the desired height, they adjust the tightness with a belt. There are also ways to make this change permanently, by sewing the fabric together. The ideal, or recommended, height of a skirt according to the dress code or protocol (which is what should apply for a school) is below the knee or slightly above it. But it turns out that there was some kind of study where they compared the height of the skirts of schoolgirls in Japan in different prefectures. And there are schools where the girls wear skirts as short as those in an anime!
Running from left to right, the listing even includes descriptive photos so readers don’t have to guess the measurements:

Shiga Prefecture: 19 centimeters above the knee.
Niigata Prefecture: 20 centimeters above the knee.
Tokyo Prefecture: 23 centimeters above the knee.
Ibaraki Prefecture: 25 centimeters above the knee.

Of course, there were comments about it in opinion forums, highlighting: “How short are the legs, that with 25 centimeters above the knee they leave nothing to the imagination?”. “Oh my gosh, I thought those girls would be wearing knee-highs. But not even that.” “That’s not even a skirt anymore, it’s a huge belt.” “I think in Sailor Moon they wore skirts that short.” “Well, I haven’t thought about this, but girls wearing those kinds of skirts are too erotic.” “Are they going to a training school for whores?” “Unbelievable, there are no schoolgirls with good legs nowadays.” “Do they want to show their panties that much?” «What is the insistence of showing the thighs? It’s not a complaint.” “I think it should no longer be measured from the knee, but from the pussy.” Fountain: Yaraon!