Head football and baseball coach at Cleveland Benedictine High School for over a quarter century, he is considered among the most successful coaches in Greater Cleveland scholastic sports annals. His first Bengal football team in 1955 enjoyed a 9-0 season, including a 47-6 victory in the City Championship game. He captured eight more city crowns and the 1957 Ohio high school championship before Benedictine left the East Senate in 1971. In 1973 and 1980 the Bengals won the Ohio Class AA state championship playoffs and Bossu was named Ohio Coach of the Year for a second time in 1973. His baseball teams have won nearly 75 percent of their contests and eight city titles. He is a member of the Ohio High School Coaches Hall of Fame.