Boston-3/26/13- Dancers from the Peter Smith School of Irish Dance from New Jersey practice their mixed under age 13 ceili dance at The World Irish Dancing Championships being held at the Hynes Convention Center. It is only the second time in it's 40 year history that the eight-day event is held outside Ireland and Scotland. Organizers expect twenty-thousand people from around the globe to attend the event. Boston Globe staff photo by John Tlumacki(metro)