Purim is celebrated by the reading of the Scroll of Esther, known in Hebrew as the Megillat Esther, which relates the basic story of Purim. Under the rule of King Ahashuerus, Haman, the King's prime minister, plots to exterminate all of the Jews of Persia. His plan is foiled by Queen Esther and her cousin Mordechai, who ultimately save the Jews of the land from destruction. The reading of the megillah is typically a rowdy affair, punctuated by booing and noise-making when Haman's name is read aloud.
Each year, the teenagers of Adat Chaverim write an original Purim Shpiel and with the help of some adults put on a production celelbrating the story of Purim. It's a big night of celebration preceeded by a Purim carnival for kids of all ages. Check the Temple calendar for specific times.