"Penkkarit"

Text is from Yle News last year:

"Throwing candy from the back of trucks while in fancy dress is an important rite of passage in Finland."

 "Century-old tradition known as "penkkarit" when upper secondary school seniors enjoy their last hurrah – the end of formal classes – before they take a break to prepare for their matriculation exams"

"Typically, the graduating students – known as "abiturientit" in Finnish or more commonly "abit" – select a theme for their costumes and banners, which range from witty one-liners to more serious social or political commentary."