In To Sir, with Love, what was Braithwaite's life like before he got the teaching job?

Part of what makes Braithwaite's account so moving is that
he does not dwell that much on his pre- teaching life.  He holds a degree in
engineering, and being the victim of a crowded field as well as due to his skin color,
Braithwaite turns to teaching as a "job."  The implication here is that his life lacked
purpose and direction prior to his entry into education.  The focus that Braithwaite
demonstrates as a teacher and advocate for students is not present in his life before
teaching, where he moved from applying to position after position.  The experience of
being denied from each one reflects the rootlessness that is not a part of his world
once he enters teaching and commits to become better at it.  In the end, I think that
this becomes one of the critical elements of the narrative.  The vagabond nature of
personal life and career are replaced by the sense of purpose and driving focus to
enhance the life of children that Braithwaite experiences as a
teacher.