This tradition is very common and i love it o(〃＾▽＾〃)o
Soo...
The thing is that when you are finishing Střední škola (High school) or uni, then you need to do final exams for it. The school is giving you a studying break before the finals and school certificate.
But that means you wont see your classmates or teachers before the exams and thats why they have Last bell.
This week students are free from school program and are going to collect money for the last party or event, in the city and school.
Often the students are having somekind of costume theme (for example Matrix or cowboys), that they are wearing all day. Sometimes students can "attack" you with waterguns or with makeup for not paying them, but if you buy from them a "free ticket" then you are safe.
I really like this tradition, because its fun and shows a creativity of the students.
