When I was in pri sch, the class would occasionally receive a pleasant surprise – candies. The treat could be from the teacher for Children’s day celebration. It could also be from a classmate who was celebrating his/her birthday. In appreciation, the class would sing the birthday song. It was a simple birthday celebration.
Things got a bit wild in sec sch. The birthday boy/girl would be lured to a place, usually the football field or basketball court, and ambushed by the good friends attacking him/her with water and flour (sometimes even eggs). In some cases, the birthday boy/girl was alert enough and tried to run away, then the friends would be chasing after him/her and they would not stop until they achieved their aim of making him/her wet. It was their idea of a memorable birthday celebration.