Among the many options for summer activities for youngsters in the United States are music camps. Some are hosted by colleges, some by music schools, and the newest was created by New York’s renowned concert venue, Carnegie Hall. This month (July), some of the best teenage musicians in the country gathered on the campus of Purchase College, outside of New York City, to create the National Youth Orchestra of the United States of America. And these young musicians are now on a tour with superstar violinist Joshua Bell and esteemed Russian conductor Valery Gergiev. Jeff Lunden spent several days with the young musicians and has this report.