Chapter 11 of To Sir, With Love is a pivotal one. In this chapter the insolent Denham wants to humiliate Mr. Braithwaite after Mr. Braithwaite tore up his magazine photo of a scantily clad young woman.
The chapter begins with the boys lining up in their blue shorts for Physical Education class on a Thursday afternoon. Denham asks, "Can't we have boxing today first, please, Sir?" When Braithwaite asks him why he has made this request, Denham casually replies that he just thinks a change would be good. But, when he tells his teacher that his partner is crippled and asks Braithwaite to "have a go with me," Braithwaite understands that there is an underlying motive in the student. Denham removes his gloves and drops them at Braithwaite's feet when he is denied the chance to box his teacher. The other boys look both disappointed and disgusted at what they perceive as cowardice in Mr. Braithwaite. "They thought I was afraid, scared of the hulkish, loutish fellow," Braithwaite narrates.
So, he decides that he must fight Denham and puts on the gloves at his feet, saying, "Okay, let's go." But, once they begin, Briathwaite realizes that he has allowed himself to be lured into a potentially compromising situation; therefore, he tries to parry and dodge as best he can until he can reasonably call an end to the match. One of the boys calls out to him to engage with Denham, disappointment in his voice. Suddenly, however, Denham delivers a stinging blow to his teacher's face. Braithwaite reacts, striking a sharp blow to the boy's solar plexus; Denham doubles over and falls to the mat. When the others rush to him, Braithwaite orders them to leave him alone and line up against the wall. He then tends to the student, sees that he is only winded, and will quickly recover. But, when he glances at the rest of the class
...they now looked at me as though I had suddenly and satisfactorily grown up before their very eyes.
After class Braithwaite checks again on Denham, telling him his was just a lucky punch and he meant no harm. When Denham replies, "Yes, Sir," there is no longer any disrespect in his tone. Braithwaite notes, "That incident marked a turning point in my relationship with the class." While Denham still made the occasional wisecrack, the disrespect was gone from his voice, as it was with the others.
Later, Braithwaite comes to understand that his students know more of life than most teens as they know about the need for money in their families and many of the girls have helped with baby siblings. So, he tries to relate his teaching to familiar things in the students' lives, such as using measurements for material, linoleum and carpet, etc. Occasionally, Mr. Florian, the headmaster, drops in and joins discussions. On one such visit, Mr. Braithwaite mentions that the students would like to go on a field trip to the Albert and Victoria Museum. The headmaster is not keen on this idea, worried that the students would misbehave, but he adds that if another teacher accompanies Braithwaite as an extra chaperone, he will give his permission. So Braithwaite asks Miss Blanchard in the staff room one day. While the teachers are still there, a student enters and tells Mr. Weston that Miss Dare would like to know if the girls' netball has been repaired. Weston is puzzled at the name; so, when the boy explains that he means Pamela Dare, Weston mocks Braithwaite for employing such formalities for the "tarts." But Miss Dawe and others come to the defense of Braithwaite.