The party to celebrate a girl's "fifteen years" is a very special party for a family in Argentina

The girl who celebrates her fifteenth birthday is entertained with a dinner-dance that lasts all night. 

If the family is Christian Catholic, a mass is officiated, in the morning or hours before the party,  to which all the guests go. The priest officiates the mass and at the end gives the blessing to the girl. She is usually dressed in a long dress (like a bride's one) and she  receives the guests who give her presents. 

The party consists of a dinner, in a big room. As the time for the toasts arrives, the presents must be opened and then the "fifteenth birthday" cake cut. This is a huge cake with "surprises" inside it, the friends take hold of one of the ribbons coming from the cake, they pull and they obtain their surprise. 

One of these surprises is usually a ring (it means: marriage!). 

After the cutting of the cake, the waltz begins. Firstly the father dances with his daughter, and is then joined by the other relatives: siblings, cousins, friends, etc. All of them dance the waltz.
When the  waltz finishes, followed by applauses, the  party continues with several dances and kind of music (it depends on the province, the zone): modern music, rock, and (in my province, in the country) with
folklore music. 

Food of the dinner depends on the place: sandwiches, chicken, and several regional foods.

The party for boys is when they are eighteen years old. But their party,
between boys, is much more simple: an "asado" (roast meat), music and dance. Perhaps followed by a football game.

My fifteenth birthday party was very funny. I spent it with my parents, my family and a lot of friends. I entered the party with my godfather. My family congratulated my friends and me too. I was very happy and emotional. 

Then I danced the traditional dance, the waltz. I danced the fifteen-year-old waltz with my father, my godfather, with my cousins and with my friends. And then the party started. We danced a lot. We ate a cold dinner and we went on dancing. Really it was very funny. 

I'll never forget my fifteen-year-old party. I'll remember it forever. 

JORGELINA SERNA . SEVENTEEN YEARS OLD. WINDLANDS SCHOOL OF ENGLISH.