In To Sir, with Love, how do the children react to getting a new teacher?

When the students see Mr. Braithwaite in their classroom, they begin to scrutinize him silently. They tensely wait for him to respond to a student who slams a desk when closing it, and no students volunteer to read Treasure Island except Pamela Dare. They are testing Braithwaite, and they are not used to any kind of discipline in the classroom. When Braithwaite asks them about the system of weights and measures, one students responds with a system of boxing weights to mock Braithwaite. What follows this period of resentment and clowning is a long period of the silent treatment in which the students do what Braithwaite asks them, but they do so without any interest or enthusiasm. This is followed by the noisy treatment, when they slam their desks when Braithwaite is trying to speak or read. Braithwaite is at first at a loss about how to reach his students.