Children ride a balloon ride in an amusement park .
Children on a balloon ride at a carnival .
Children ride a balloon ride in an amusement park.
Children on a balloon ride at a carnival.
Being on a balloon ride is a restatement of ride a balloon ride.  A carnival is another name for amusement park.
Being on a balloon ride is a restatement of ride a balloon ride . A carnival is another name for amusement park .