in the U.S. today 30% of all children are overweight.This can be very unhealthy and dangerous,too.Many parents want to prevent this.Therefore,some parent bring their young children to exercise classes to help their children stay healthy.In fact,some infants who are only a few weeks old can attend these classes,too!These parent want their children to enjoy exercise.They hope that their children will grow up to become adults who enjoy exercise,too.