He was lazy, slept in class, loitered outside after school and occasionally got into fights.
He was also not interested in his studies and had to repeat his O levels.
At 18, Mr Roy Chew joined the Institute of Technical Education's (ITE) Certificate in Business studies (Accounting) while continuing to work part-time.
He finally buckled down and at the age of 40, Mr Chew will be graduating from Nanyang Technological University with a master's in marketing and Asian consumer insights in July.
Now a deputy director at the People's Association, Mr Chew grew up in a three-room flat in Ang Mo Kio with his two sisters, grandparents and parents.
When still a student at Bowen Secondary School, Mr Chew had to work part-time and usually reached home after 10pm.
He said: "At that time, I felt disappointed and ashamed because my older sister had already set the bar."
She had done well enough in her studies to enter a junior college and later the National University of Singapore.
Mr Chew signed on with the Singapore Police Force after he left ITE to earn a stable income.
When he turned 27, the police sponsored him to do a diploma in management and police studies at Temasek Polytechnic.
The stint opened his eyes. He saw that what he learnt in school could be applied in daily life.
He said: "The management modules I learnt were relevant to my police work. I gained new perspectives and this made me more hungry for knowledge.
"I wanted to catch up on lost time..."
The process of learning was refreshing for him.
Mr Chew said: "There were too many things I didn't know. I gained new perspectives and this fuelled my hunger."
At 30, he obtained his first degree, a bachelor's with honours in marketing at MDIS.
Mr Chew now has two daughters, aged eight and two, with his 37-year-old housewife.
He said: "(Sometimes, when studying for my master's) I had 15 consecutive full-day classes. It was very painful, because I had to juggle work and the birth of my second child.
"But I've been through hardship before and I knew the only way was to press on.
"My hardship kept me grounded and made me tougher in overcoming challenges. If the challenge is tough, I'll be tougher to overcome them."
Mr R Ravindaran, section head of physical education (PE) at ITE College Central, said of Mr Chew: "He was a dedicated, determined and disciplined student who always gave his best.
"He is a highly motivated individual and it's heartening to know he has done well."
This article was first published on February 27, 2017.
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