Why are they everywhere now?
And why are they drinking the whole time?
Well, they are happy and drunk because they finished their 3 years in Gymnasium, Technical Gymnasium or a bunch of other schools similar to that. Here is an illustration of the various types of hats! The most common are the red and blue. The black depends on either family traditions or traditions on the school you graduate from. Some schools dedicate the black hat to mathematical students, some to greek/latin students, some to elite students. The illustration i borrowed from Politiken.dk.
There are plenty of traditions for the hats. Your friends should bite the black part of the hat and then write something inside the hat for you. Your final grade will be written in the middle of the inside of the hat where there is usually a gold version of your schools logo. If your boy/girlfriend write their name in the gold, you will eventually marry them. There is also a "secret" part of the hat for dirty messages. Ooohh! There is a ton of other rules about cutting out stuff of the hat. Bathe naked, cut a wave in the inside of the hat. Drink a case of beer, cut a square in the inside of the hat. Watch a sunrise, cut a triangle. And about 50 other ones, differing from school to school.
They will be happy and proud to tell you about their hats, and even more so if you congratulate them. It is common for strangers to congratulate the new students on their hats. This week, most of them has been partying all day and night since they finished their final exam.
Tomorrow and saturday, it will get even more weird. They usually gather at their school in the morning for their graduation ceremony - after that, decorated open trucks will wait for them and they will go and visit everyone from their class in the truck. Where I'm from, all the students then drive to the fountain downtown to dance around it. The student with the highest grade average will be thrown in the fountain! In Copenhagen, they will dance around Storkespringvandet on Strøget! After that, the tour starts! A drink and a snack at all the places, then back to the truck with music playing and beer provided by the girl in class with the largest head and the boy with the smallest head.
The truck is usually decorated by the class a year below the graduated class. They also provide a case of beer. Birch branches, flags, balloons and banners are the common decorations. The banners are usually naughty! Some of them tells dirty stories of the graduated class, most of them tell the cars passing by to honk for the students to flash. Therefore, a lot of honking is to be heard on the Danish roads tomorrow!
There are usually some 20 students in each class, so the driving takes all day and usually they continue until the morning after. Therefore many of the bars in Copenhagen will be even more fun to go to! More people partying like crazy! They might be young but they are also a lot of fun - at least to observe!
"We puke in your back yards"