Marc Yu, 7, is living the life of a rock star. That is, a rock star who plays classical piano. He has performed sold-out concerts to cheering crowds. Last week, the hard work behind his success was revealed in a documentary on The Learning Channel called My Life as a Child. He has also been on numerous other TV shows. Marc says his most treasured concert was in Hong Kong, where he performed with his hero, Chinese pianist Lang Lang. "It was a dream of mine for years," Marc told TFK.