Final answer:
In 'Lean on Me', Mr. Clark first addressed the teachers, setting the tone for his administration and emphasizing the significant role teachers have in education.
Step-by-step explanation:
In the movie Lean on Me, Mr. Clark, played by Morgan Freeman, addressed the teachers first when he took over as principal of Eastside High School. This initial meeting is significant as it sets the tone for Mr. Clark's administration and his approach to reforming the school. He speaks directly to the the teachers to inform them of the new rules and expectations that will be in place under his leadership. The film underscores the importance of school leadership and the pivotal role that the teachers play in the educational environment.