The Pennsylvania Ballet returns to the McCarter stage for the first time in almost a decade—and it’s high time! Under the artistic direction of Roy Kaiser, the company will celebrate its 50th anniversary next year, and has remained true to its origins as a home for classically trained dancers with individual looks and presences. Always the toast of Philadelphia, its dancers have a can-do attitude about eclecticism, long a favored goal of America’s best ballet companies. Their program will include New York Export: Opus Jazz, by Jerome Robbins, and Peter Martins’ Barber Violin Concerto, and Square Dance by George Balanchine.