The source shows a student pass for one that is studying Japanese. This meant that the Japanese forced the individuals to study Japanese, and the Japanese only permitted certain topics to be taught. This shows the daily lives of teenagers were controlled by Japanese officials and teenagers had only the choice to study Japanese and had no freedom to choose what to pursue.
The source tells of a 13 year old during the Occupation, Chin Sin Chong, who had to find work and tried to carry on with his studies during the Occupation. He faced several challenges finding work, shifting from one job to another just to satisfy his financial needs. This shows that many of the teenagers' lives were tough and in poor conditions, where they had to take charge of their lives financially and physically.
The source shows a Japanese official requesting the support of the people with the words 'Shake hands with us'. This shows the propaganda the Japanese had set up to win over peoples' support. Teenagers were especially exposed to these as they were young and impressionable, and many of the schools screened propaganda and made the students believe in the Japanese. This shows that the Japanese took control of teenagers in the Occupation, by making them fall for the trap of putting their faith in the Japanese.
The source shows identity cards of students who went to work under the Japanese. This means that the Japanese had teenagers already working even at ages of 13, and that teenagers were pressured to find jobs to support their families. They had to adapt and change from the easygoing life before the Occupation.