"Swing Kids" involves a very small footnote to a very large historical event. In Nazi Germany in 1939, we learn, while Hitler was rounding up Jews and launching World War II, a small group of kids wore their hair long and danced to the swing music of such banned musicians as Benny Goodman and Count Basie. Occasionally they got into fights with the brownshirts of the Hitler Youth brigades. If the Swing Kids had evolved into an underground movement dedicated to the overthrow of Nazism, we might be onto something here. But no. A title card at the end of the film informs us that some of the kids ...