"I will never look at the Duluth-Superior Harbor again in the same way," said Sarah Pregitzer, a sixth-grade science teacher at Grant Middle School for the past 32 years who participated recently in an educational program on the Great Lakes/St. Lawrence Seaway shipping industry. "It's fascinating to know all that is going on." Most teachers, students and Great Lakes residents have little knowledge of the maritime transportation industry operating on the Great Lakes and the essential role that shipping plays in the state, U.S. and world economy by providing many of the household products used daily.